Persist counterparty skimmed fee in ClaimableHTLC
[rust-lightning] / lightning / src / ln / channelmanager.rs
index de12812544aa795bf0f8e5e3f7f2c1283d9a85ac..808c7ffcd3ac2196e5961f406f13d5f347fee0c5 100644 (file)
@@ -19,7 +19,7 @@
 
 use bitcoin::blockdata::block::BlockHeader;
 use bitcoin::blockdata::transaction::Transaction;
-use bitcoin::blockdata::constants::genesis_block;
+use bitcoin::blockdata::constants::{genesis_block, ChainHash};
 use bitcoin::network::constants::Network;
 
 use bitcoin::hashes::Hash;
@@ -36,17 +36,17 @@ use crate::chain::chaininterface::{BroadcasterInterface, ConfirmationTarget, Fee
 use crate::chain::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, ChannelMonitorUpdateStep, HTLC_FAIL_BACK_BUFFER, CLTV_CLAIM_BUFFER, LATENCY_GRACE_PERIOD_BLOCKS, ANTI_REORG_DELAY, MonitorEvent, CLOSED_CHANNEL_UPDATE_ID};
 use crate::chain::transaction::{OutPoint, TransactionData};
 use crate::events;
-use crate::events::{Event, EventHandler, EventsProvider, MessageSendEvent, MessageSendEventsProvider, ClosureReason, HTLCDestination};
+use crate::events::{Event, EventHandler, EventsProvider, MessageSendEvent, MessageSendEventsProvider, ClosureReason, HTLCDestination, PaymentFailureReason};
 // Since this struct is returned in `list_channels` methods, expose it here in case users want to
 // construct one themselves.
 use crate::ln::{inbound_payment, PaymentHash, PaymentPreimage, PaymentSecret};
-use crate::ln::channel::{Channel, ChannelError, ChannelUpdateStatus, UpdateFulfillCommitFetch};
+use crate::ln::channel::{Channel, ChannelContext, ChannelError, ChannelUpdateStatus, ShutdownResult, UpdateFulfillCommitFetch, OutboundV1Channel, InboundV1Channel};
 use crate::ln::features::{ChannelFeatures, ChannelTypeFeatures, InitFeatures, NodeFeatures};
 #[cfg(any(feature = "_test_utils", test))]
 use crate::ln::features::InvoiceFeatures;
 use crate::routing::gossip::NetworkGraph;
-use crate::routing::router::{DefaultRouter, InFlightHtlcs, PaymentParameters, Route, RouteHop, RouteParameters, RoutePath, Router};
-use crate::routing::scoring::ProbabilisticScorer;
+use crate::routing::router::{BlindedTail, DefaultRouter, InFlightHtlcs, Path, Payee, PaymentParameters, Route, RouteHop, RouteParameters, Router};
+use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
 use crate::ln::msgs;
 use crate::ln::onion_utils;
 use crate::ln::onion_utils::HTLCFailReason;
@@ -55,8 +55,8 @@ use crate::ln::msgs::{ChannelMessageHandler, DecodeError, LightningError, MAX_VA
 use crate::ln::outbound_payment;
 use crate::ln::outbound_payment::{OutboundPayments, PaymentAttempts, PendingOutboundPayment};
 use crate::ln::wire::Encode;
-use crate::chain::keysinterface::{EntropySource, KeysManager, NodeSigner, Recipient, SignerProvider, ChannelSigner, WriteableEcdsaChannelSigner};
-use crate::util::config::{UserConfig, ChannelConfig};
+use crate::sign::{EntropySource, KeysManager, NodeSigner, Recipient, SignerProvider, ChannelSigner, WriteableEcdsaChannelSigner};
+use crate::util::config::{UserConfig, ChannelConfig, ChannelConfigUpdate};
 use crate::util::wakers::{Future, Notifier};
 use crate::util::scid_utils::fake_scid;
 use crate::util::string::UntrustedString;
@@ -72,12 +72,13 @@ use core::{cmp, mem};
 use core::cell::RefCell;
 use crate::io::Read;
 use crate::sync::{Arc, Mutex, RwLock, RwLockReadGuard, FairRwLock, LockTestExt, LockHeldState};
-use core::sync::atomic::{AtomicUsize, Ordering};
+use core::sync::atomic::{AtomicUsize, AtomicBool, Ordering};
 use core::time::Duration;
 use core::ops::Deref;
 
 // Re-export this for use in the public API.
-pub use crate::ln::outbound_payment::{PaymentSendFailure, Retry, RetryableSendFailure};
+pub use crate::ln::outbound_payment::{PaymentSendFailure, Retry, RetryableSendFailure, RecipientOnionFields};
+use crate::ln::script::ShutdownScript;
 
 // We hold various information about HTLC relay in the HTLC objects in Channel itself:
 //
@@ -106,11 +107,15 @@ pub(super) enum PendingHTLCRouting {
        },
        Receive {
                payment_data: msgs::FinalOnionHopData,
+               payment_metadata: Option<Vec<u8>>,
                incoming_cltv_expiry: u32, // Used to track when we should expire pending HTLCs that go unclaimed
                phantom_shared_secret: Option<[u8; 32]>,
        },
        ReceiveKeysend {
+               /// This was added in 0.0.116 and will break deserialization on downgrades.
+               payment_data: Option<msgs::FinalOnionHopData>,
                payment_preimage: PaymentPreimage,
+               payment_metadata: Option<Vec<u8>>,
                incoming_cltv_expiry: u32, // Used to track when we should expire pending HTLCs that go unclaimed
        },
 }
@@ -126,6 +131,9 @@ pub(super) struct PendingHTLCInfo {
        /// may overshoot this in either case)
        pub(super) outgoing_amt_msat: u64,
        pub(super) outgoing_cltv_value: u32,
+       /// The fee being skimmed off the top of this HTLC. If this is a forward, it'll be the fee we are
+       /// skimming. If we're receiving this HTLC, it's the fee that our counterparty skimmed.
+       pub(super) skimmed_fee_msat: Option<u64>,
 }
 
 #[derive(Clone)] // See Channel::revoke_and_ack for why, tl;dr: Rust bug
@@ -205,6 +213,8 @@ struct ClaimableHTLC {
        total_value_received: Option<u64>,
        /// The sender intended sum total of all MPP parts specified in the onion
        total_msat: u64,
+       /// The extra fee our counterparty skimmed off the top of this HTLC.
+       counterparty_skimmed_fee_msat: Option<u64>,
 }
 
 /// A payment identifier used to uniquely identify a payment to LDK.
@@ -280,13 +290,12 @@ impl_writeable_tlv_based_enum!(SentHTLCId,
 pub(crate) enum HTLCSource {
        PreviousHopData(HTLCPreviousHopData),
        OutboundRoute {
-               path: Vec<RouteHop>,
+               path: Path,
                session_priv: SecretKey,
                /// Technically we can recalculate this from the route, but we cache it here to avoid
                /// doing a double-pass on route when we get a failure back
                first_hop_htlc_msat: u64,
                payment_id: PaymentId,
-               payment_secret: Option<PaymentSecret>,
        },
 }
 #[allow(clippy::derive_hash_xor_eq)] // Our Hash is faithful to the data, we just don't have SecretKey::hash
@@ -297,27 +306,37 @@ impl core::hash::Hash for HTLCSource {
                                0u8.hash(hasher);
                                prev_hop_data.hash(hasher);
                        },
-                       HTLCSource::OutboundRoute { path, session_priv, payment_id, payment_secret, first_hop_htlc_msat } => {
+                       HTLCSource::OutboundRoute { path, session_priv, payment_id, first_hop_htlc_msat } => {
                                1u8.hash(hasher);
                                path.hash(hasher);
                                session_priv[..].hash(hasher);
                                payment_id.hash(hasher);
-                               payment_secret.hash(hasher);
                                first_hop_htlc_msat.hash(hasher);
                        },
                }
        }
 }
-#[cfg(not(feature = "grind_signatures"))]
-#[cfg(test)]
 impl HTLCSource {
+       #[cfg(not(feature = "grind_signatures"))]
+       #[cfg(test)]
        pub fn dummy() -> Self {
                HTLCSource::OutboundRoute {
-                       path: Vec::new(),
+                       path: Path { hops: Vec::new(), blinded_tail: None },
                        session_priv: SecretKey::from_slice(&[1; 32]).unwrap(),
                        first_hop_htlc_msat: 0,
                        payment_id: PaymentId([2; 32]),
-                       payment_secret: None,
+               }
+       }
+
+       #[cfg(debug_assertions)]
+       /// Checks whether this HTLCSource could possibly match the given HTLC output in a commitment
+       /// transaction. Useful to ensure different datastructures match up.
+       pub(crate) fn possibly_matches_output(&self, htlc: &super::chan_utils::HTLCOutputInCommitment) -> bool {
+               if let HTLCSource::OutboundRoute { first_hop_htlc_msat, .. } = self {
+                       *first_hop_htlc_msat == htlc.amount_msat
+               } else {
+                       // There's nothing we can check for forwarded HTLCs
+                       true
                }
        }
 }
@@ -347,8 +366,6 @@ pub enum FailureCode {
        IncorrectOrUnknownPaymentDetails = 0x4000 | 15,
 }
 
-type ShutdownResult = (Option<(OutPoint, ChannelMonitorUpdate)>, Vec<(HTLCSource, PaymentHash, PublicKey, [u8; 32])>);
-
 /// Error type returned across the peer_state mutex boundary. When an Err is generated for a
 /// Channel, we generally end up with a ChannelError::Close for which we have to close the channel
 /// immediately (ie with no further calls on it made). Thus, this step happens inside a
@@ -461,6 +478,12 @@ impl_writeable_tlv_based!(ClaimingPayment, {
        (4, receiver_node_id, required),
 });
 
+struct ClaimablePayment {
+       purpose: events::PaymentPurpose,
+       onion_fields: Option<RecipientOnionFields>,
+       htlcs: Vec<ClaimableHTLC>,
+}
+
 /// Information about claimable or being-claimed payments
 struct ClaimablePayments {
        /// Map from payment hash to the payment data and any HTLCs which are to us and can be
@@ -471,7 +494,7 @@ struct ClaimablePayments {
        ///
        /// When adding to the map, [`Self::pending_claiming_payments`] must also be checked to ensure
        /// we don't get a duplicate payment.
-       claimable_htlcs: HashMap<PaymentHash, (events::PaymentPurpose, Vec<ClaimableHTLC>)>,
+       claimable_payments: HashMap<PaymentHash, ClaimablePayment>,
 
        /// Map from payment hash to the payment data for HTLCs which we have begun claiming, but which
        /// are waiting on a [`ChannelMonitorUpdate`] to complete in order to be surfaced to the user
@@ -479,13 +502,34 @@ struct ClaimablePayments {
        pending_claiming_payments: HashMap<PaymentHash, ClaimingPayment>,
 }
 
-/// Events which we process internally but cannot be procsesed immediately at the generation site
-/// for some reason. They are handled in timer_tick_occurred, so may be processed with
-/// quite some time lag.
+/// Events which we process internally but cannot be processed immediately at the generation site
+/// usually because we're running pre-full-init. They are handled immediately once we detect we are
+/// running normally, and specifically must be processed before any other non-background
+/// [`ChannelMonitorUpdate`]s are applied.
 enum BackgroundEvent {
-       /// Handle a ChannelMonitorUpdate that closes a channel, broadcasting its current latest holder
-       /// commitment transaction.
-       ClosingMonitorUpdate((OutPoint, ChannelMonitorUpdate)),
+       /// Handle a ChannelMonitorUpdate which closes the channel. This is only separated from
+       /// [`Self::MonitorUpdateRegeneratedOnStartup`] as the maybe-non-closing variant needs a public
+       /// key to handle channel resumption, whereas if the channel has been force-closed we do not
+       /// need the counterparty node_id.
+       ///
+       /// Note that any such events are lost on shutdown, so in general they must be updates which
+       /// are regenerated on startup.
+       ClosingMonitorUpdateRegeneratedOnStartup((OutPoint, ChannelMonitorUpdate)),
+       /// Handle a ChannelMonitorUpdate which may or may not close the channel and may unblock the
+       /// channel to continue normal operation.
+       ///
+       /// In general this should be used rather than
+       /// [`Self::ClosingMonitorUpdateRegeneratedOnStartup`], however in cases where the
+       /// `counterparty_node_id` is not available as the channel has closed from a [`ChannelMonitor`]
+       /// error the other variant is acceptable.
+       ///
+       /// Note that any such events are lost on shutdown, so in general they must be updates which
+       /// are regenerated on startup.
+       MonitorUpdateRegeneratedOnStartup {
+               counterparty_node_id: PublicKey,
+               funding_txo: OutPoint,
+               update: ChannelMonitorUpdate
+       },
 }
 
 #[derive(Debug)]
@@ -495,23 +539,95 @@ pub(crate) enum MonitorUpdateCompletionAction {
        /// this payment. Note that this is only best-effort. On restart it's possible such a duplicate
        /// event can be generated.
        PaymentClaimed { payment_hash: PaymentHash },
-       /// Indicates an [`events::Event`] should be surfaced to the user.
-       EmitEvent { event: events::Event },
+       /// Indicates an [`events::Event`] should be surfaced to the user and possibly resume the
+       /// operation of another channel.
+       ///
+       /// This is usually generated when we've forwarded an HTLC and want to block the outbound edge
+       /// from completing a monitor update which removes the payment preimage until the inbound edge
+       /// completes a monitor update containing the payment preimage. In that case, after the inbound
+       /// edge completes, we will surface an [`Event::PaymentForwarded`] as well as unblock the
+       /// outbound edge.
+       EmitEventAndFreeOtherChannel {
+               event: events::Event,
+               downstream_counterparty_and_funding_outpoint: Option<(PublicKey, OutPoint, RAAMonitorUpdateBlockingAction)>,
+       },
 }
 
 impl_writeable_tlv_based_enum_upgradable!(MonitorUpdateCompletionAction,
        (0, PaymentClaimed) => { (0, payment_hash, required) },
-       (2, EmitEvent) => { (0, event, upgradable_required) },
+       (2, EmitEventAndFreeOtherChannel) => {
+               (0, event, upgradable_required),
+               // LDK prior to 0.0.116 did not have this field as the monitor update application order was
+               // required by clients. If we downgrade to something prior to 0.0.116 this may result in
+               // monitor updates which aren't properly blocked or resumed, however that's fine - we don't
+               // support async monitor updates even in LDK 0.0.116 and once we do we'll require no
+               // downgrades to prior versions.
+               (1, downstream_counterparty_and_funding_outpoint, option),
+       },
 );
 
+#[derive(Clone, Debug, PartialEq, Eq)]
+pub(crate) enum EventCompletionAction {
+       ReleaseRAAChannelMonitorUpdate {
+               counterparty_node_id: PublicKey,
+               channel_funding_outpoint: OutPoint,
+       },
+}
+impl_writeable_tlv_based_enum!(EventCompletionAction,
+       (0, ReleaseRAAChannelMonitorUpdate) => {
+               (0, channel_funding_outpoint, required),
+               (2, counterparty_node_id, required),
+       };
+);
+
+#[derive(Clone, PartialEq, Eq, Debug)]
+/// If something is blocked on the completion of an RAA-generated [`ChannelMonitorUpdate`] we track
+/// the blocked action here. See enum variants for more info.
+pub(crate) enum RAAMonitorUpdateBlockingAction {
+       /// A forwarded payment was claimed. We block the downstream channel completing its monitor
+       /// update which removes the HTLC preimage until the upstream channel has gotten the preimage
+       /// durably to disk.
+       ForwardedPaymentInboundClaim {
+               /// The upstream channel ID (i.e. the inbound edge).
+               channel_id: [u8; 32],
+               /// The HTLC ID on the inbound edge.
+               htlc_id: u64,
+       },
+}
+
+impl RAAMonitorUpdateBlockingAction {
+       #[allow(unused)]
+       fn from_prev_hop_data(prev_hop: &HTLCPreviousHopData) -> Self {
+               Self::ForwardedPaymentInboundClaim {
+                       channel_id: prev_hop.outpoint.to_channel_id(),
+                       htlc_id: prev_hop.htlc_id,
+               }
+       }
+}
+
+impl_writeable_tlv_based_enum!(RAAMonitorUpdateBlockingAction,
+       (0, ForwardedPaymentInboundClaim) => { (0, channel_id, required), (2, htlc_id, required) }
+;);
+
+
 /// State we hold per-peer.
 pub(super) struct PeerState<Signer: ChannelSigner> {
-       /// `temporary_channel_id` or `channel_id` -> `channel`.
+       /// `channel_id` -> `Channel`.
        ///
-       /// Holds all channels where the peer is the counterparty. Once a channel has been assigned a
-       /// `channel_id`, the `temporary_channel_id` key in the map is updated and is replaced by the
-       /// `channel_id`.
+       /// Holds all funded channels where the peer is the counterparty.
        pub(super) channel_by_id: HashMap<[u8; 32], Channel<Signer>>,
+       /// `temporary_channel_id` -> `OutboundV1Channel`.
+       ///
+       /// Holds all outbound V1 channels where the peer is the counterparty. Once an outbound channel has
+       /// been assigned a `channel_id`, the entry in this map is removed and one is created in
+       /// `channel_by_id`.
+       pub(super) outbound_v1_channel_by_id: HashMap<[u8; 32], OutboundV1Channel<Signer>>,
+       /// `temporary_channel_id` -> `InboundV1Channel`.
+       ///
+       /// Holds all inbound V1 channels where the peer is the counterparty. Once an inbound channel has
+       /// been assigned a `channel_id`, the entry in this map is removed and one is created in
+       /// `channel_by_id`.
+       pub(super) inbound_v1_channel_by_id: HashMap<[u8; 32], InboundV1Channel<Signer>>,
        /// The latest `InitFeatures` we heard from the peer.
        latest_features: InitFeatures,
        /// Messages to send to the peer - pushed to in the same lock that they are generated in (except
@@ -532,6 +648,11 @@ pub(super) struct PeerState<Signer: ChannelSigner> {
        /// to funding appearing on-chain), the downstream `ChannelMonitor` set is required to ensure
        /// duplicates do not occur, so such channels should fail without a monitor update completing.
        monitor_update_blocked_actions: BTreeMap<[u8; 32], Vec<MonitorUpdateCompletionAction>>,
+       /// If another channel's [`ChannelMonitorUpdate`] needs to complete before a channel we have
+       /// with this peer can complete an RAA [`ChannelMonitorUpdate`] (e.g. because the RAA update
+       /// will remove a preimage that needs to be durably in an upstream channel first), we put an
+       /// entry here to note that the channel with the key's ID is blocked on a set of actions.
+       actions_blocking_raa_monitor_updates: BTreeMap<[u8; 32], Vec<RAAMonitorUpdateBlockingAction>>,
        /// The peer is currently connected (i.e. we've seen a
        /// [`ChannelMessageHandler::peer_connected`] and no corresponding
        /// [`ChannelMessageHandler::peer_disconnected`].
@@ -548,6 +669,20 @@ impl <Signer: ChannelSigner> PeerState<Signer> {
                }
                self.channel_by_id.is_empty() && self.monitor_update_blocked_actions.is_empty()
        }
+
+       // Returns a count of all channels we have with this peer, including pending channels.
+       fn total_channel_count(&self) -> usize {
+               self.channel_by_id.len() +
+                       self.outbound_v1_channel_by_id.len() +
+                       self.inbound_v1_channel_by_id.len()
+       }
+
+       // Returns a bool indicating if the given `channel_id` matches a channel we have with this peer.
+       fn has_channel(&self, channel_id: &[u8; 32]) -> bool {
+               self.channel_by_id.contains_key(channel_id) ||
+                       self.outbound_v1_channel_by_id.contains_key(channel_id) ||
+                       self.inbound_v1_channel_by_id.contains_key(channel_id)
+       }
 }
 
 /// Stores a PaymentSecret and any other data we may need to validate an inbound payment is
@@ -591,7 +726,9 @@ pub type SimpleArcChannelManager<M, T, F, L> = ChannelManager<
        Arc<DefaultRouter<
                Arc<NetworkGraph<Arc<L>>>,
                Arc<L>,
-               Arc<Mutex<ProbabilisticScorer<Arc<NetworkGraph<Arc<L>>>, Arc<L>>>>
+               Arc<Mutex<ProbabilisticScorer<Arc<NetworkGraph<Arc<L>>>, Arc<L>>>>,
+               ProbabilisticScoringFeeParameters,
+               ProbabilisticScorer<Arc<NetworkGraph<Arc<L>>>, Arc<L>>,
        >>,
        Arc<L>
 >;
@@ -607,7 +744,66 @@ pub type SimpleArcChannelManager<M, T, F, L> = ChannelManager<
 /// of [`KeysManager`] and [`DefaultRouter`].
 ///
 /// This is not exported to bindings users as Arcs don't make sense in bindings
-pub type SimpleRefChannelManager<'a, 'b, 'c, 'd, 'e, 'f, 'g, 'h, M, T, F, L> = ChannelManager<&'a M, &'b T, &'c KeysManager, &'c KeysManager, &'c KeysManager, &'d F, &'e DefaultRouter<&'f NetworkGraph<&'g L>, &'g L, &'h Mutex<ProbabilisticScorer<&'f NetworkGraph<&'g L>, &'g L>>>, &'g L>;
+pub type SimpleRefChannelManager<'a, 'b, 'c, 'd, 'e, 'f, 'g, 'h, M, T, F, L> = ChannelManager<&'a M, &'b T, &'c KeysManager, &'c KeysManager, &'c KeysManager, &'d F, &'e DefaultRouter<&'f NetworkGraph<&'g L>, &'g L, &'h Mutex<ProbabilisticScorer<&'f NetworkGraph<&'g L>, &'g L>>, ProbabilisticScoringFeeParameters, ProbabilisticScorer<&'f NetworkGraph<&'g L>, &'g L>>, &'g L>;
+
+macro_rules! define_test_pub_trait { ($vis: vis) => {
+/// A trivial trait which describes any [`ChannelManager`] used in testing.
+$vis trait AChannelManager {
+       type Watch: chain::Watch<Self::Signer> + ?Sized;
+       type M: Deref<Target = Self::Watch>;
+       type Broadcaster: BroadcasterInterface + ?Sized;
+       type T: Deref<Target = Self::Broadcaster>;
+       type EntropySource: EntropySource + ?Sized;
+       type ES: Deref<Target = Self::EntropySource>;
+       type NodeSigner: NodeSigner + ?Sized;
+       type NS: Deref<Target = Self::NodeSigner>;
+       type Signer: WriteableEcdsaChannelSigner + Sized;
+       type SignerProvider: SignerProvider<Signer = Self::Signer> + ?Sized;
+       type SP: Deref<Target = Self::SignerProvider>;
+       type FeeEstimator: FeeEstimator + ?Sized;
+       type F: Deref<Target = Self::FeeEstimator>;
+       type Router: Router + ?Sized;
+       type R: Deref<Target = Self::Router>;
+       type Logger: Logger + ?Sized;
+       type L: Deref<Target = Self::Logger>;
+       fn get_cm(&self) -> &ChannelManager<Self::M, Self::T, Self::ES, Self::NS, Self::SP, Self::F, Self::R, Self::L>;
+}
+} }
+#[cfg(any(test, feature = "_test_utils"))]
+define_test_pub_trait!(pub);
+#[cfg(not(any(test, feature = "_test_utils")))]
+define_test_pub_trait!(pub(crate));
+impl<M: Deref, T: Deref, ES: Deref, NS: Deref, SP: Deref, F: Deref, R: Deref, L: Deref> AChannelManager
+for ChannelManager<M, T, ES, NS, SP, F, R, L>
+where
+       M::Target: chain::Watch<<SP::Target as SignerProvider>::Signer>,
+       T::Target: BroadcasterInterface,
+       ES::Target: EntropySource,
+       NS::Target: NodeSigner,
+       SP::Target: SignerProvider,
+       F::Target: FeeEstimator,
+       R::Target: Router,
+       L::Target: Logger,
+{
+       type Watch = M::Target;
+       type M = M;
+       type Broadcaster = T::Target;
+       type T = T;
+       type EntropySource = ES::Target;
+       type ES = ES;
+       type NodeSigner = NS::Target;
+       type NS = NS;
+       type Signer = <SP::Target as SignerProvider>::Signer;
+       type SignerProvider = SP::Target;
+       type SP = SP;
+       type FeeEstimator = F::Target;
+       type F = F;
+       type Router = R::Target;
+       type R = R;
+       type Logger = L::Target;
+       type L = L;
+       fn get_cm(&self) -> &ChannelManager<M, T, ES, NS, SP, F, R, L> { self }
+}
 
 /// Manager which keeps track of a number of channels and sends messages to the appropriate
 /// channel, also tracking HTLC preimages and forwarding onion packets appropriately.
@@ -860,9 +1056,31 @@ where
        #[cfg(any(test, feature = "_test_utils"))]
        pub(super) per_peer_state: FairRwLock<HashMap<PublicKey, Mutex<PeerState<<SP::Target as SignerProvider>::Signer>>>>,
 
+       /// The set of events which we need to give to the user to handle. In some cases an event may
+       /// require some further action after the user handles it (currently only blocking a monitor
+       /// update from being handed to the user to ensure the included changes to the channel state
+       /// are handled by the user before they're persisted durably to disk). In that case, the second
+       /// element in the tuple is set to `Some` with further details of the action.
+       ///
+       /// Note that events MUST NOT be removed from pending_events after deserialization, as they
+       /// could be in the middle of being processed without the direct mutex held.
+       ///
        /// See `ChannelManager` struct-level documentation for lock order requirements.
-       pending_events: Mutex<Vec<events::Event>>,
+       pending_events: Mutex<VecDeque<(events::Event, Option<EventCompletionAction>)>>,
+       /// A simple atomic flag to ensure only one task at a time can be processing events asynchronously.
+       pending_events_processor: AtomicBool,
+
+       /// If we are running during init (either directly during the deserialization method or in
+       /// block connection methods which run after deserialization but before normal operation) we
+       /// cannot provide the user with [`ChannelMonitorUpdate`]s through the normal update flow -
+       /// prior to normal operation the user may not have loaded the [`ChannelMonitor`]s into their
+       /// [`ChainMonitor`] and thus attempting to update it will fail or panic.
+       ///
+       /// Thus, we place them here to be handled as soon as possible once we are running normally.
+       ///
        /// See `ChannelManager` struct-level documentation for lock order requirements.
+       ///
+       /// [`ChainMonitor`]: crate::chain::chainmonitor::ChainMonitor
        pending_background_events: Mutex<Vec<BackgroundEvent>>,
        /// Used when we have to take a BIG lock to make sure everything is self-consistent.
        /// Essentially just when we're serializing ourselves out.
@@ -872,6 +1090,9 @@ where
        /// Notifier the lock contains sends out a notification when the lock is released.
        total_consistency_lock: RwLock<()>,
 
+       #[cfg(debug_assertions)]
+       background_events_processed_since_startup: AtomicBool,
+
        persistence_notifier: Notifier,
 
        entropy_source: ES,
@@ -898,6 +1119,7 @@ pub struct ChainParameters {
 }
 
 #[derive(Copy, Clone, PartialEq)]
+#[must_use]
 enum NotifyOption {
        DoPersist,
        SkipPersist,
@@ -921,10 +1143,20 @@ struct PersistenceNotifierGuard<'a, F: Fn() -> NotifyOption> {
 }
 
 impl<'a> PersistenceNotifierGuard<'a, fn() -> NotifyOption> { // We don't care what the concrete F is here, it's unused
-       fn notify_on_drop(lock: &'a RwLock<()>, notifier: &'a Notifier) -> PersistenceNotifierGuard<'a, impl Fn() -> NotifyOption> {
-               PersistenceNotifierGuard::optionally_notify(lock, notifier, || -> NotifyOption { NotifyOption::DoPersist })
+       fn notify_on_drop<C: AChannelManager>(cm: &'a C) -> PersistenceNotifierGuard<'a, impl Fn() -> NotifyOption> {
+               let read_guard = cm.get_cm().total_consistency_lock.read().unwrap();
+               let _ = cm.get_cm().process_background_events(); // We always persist
+
+               PersistenceNotifierGuard {
+                       persistence_notifier: &cm.get_cm().persistence_notifier,
+                       should_persist: || -> NotifyOption { NotifyOption::DoPersist },
+                       _read_guard: read_guard,
+               }
+
        }
 
+       /// Note that if any [`ChannelMonitorUpdate`]s are possibly generated,
+       /// [`ChannelManager::process_background_events`] MUST be called first.
        fn optionally_notify<F: Fn() -> NotifyOption>(lock: &'a RwLock<()>, notifier: &'a Notifier, persist_check: F) -> PersistenceNotifierGuard<'a, F> {
                let read_guard = lock.read().unwrap();
 
@@ -1006,6 +1238,14 @@ pub(crate) const MPP_TIMEOUT_TICKS: u8 = 3;
 /// [`OutboundPayments::remove_stale_resolved_payments`].
 pub(crate) const IDEMPOTENCY_TIMEOUT_TICKS: u8 = 7;
 
+/// The number of ticks of [`ChannelManager::timer_tick_occurred`] where a peer is disconnected
+/// until we mark the channel disabled and gossip the update.
+pub(crate) const DISABLE_GOSSIP_TICKS: u8 = 10;
+
+/// The number of ticks of [`ChannelManager::timer_tick_occurred`] where a peer is connected until
+/// we mark the channel enabled and gossip the update.
+pub(crate) const ENABLE_GOSSIP_TICKS: u8 = 5;
+
 /// The maximum number of unfunded channels we can have per-peer before we start rejecting new
 /// (inbound) ones. The number of peers with unfunded channels is limited separately in
 /// [`MAX_UNFUNDED_CHANNEL_PEERS`].
@@ -1164,8 +1404,14 @@ pub struct ChannelDetails {
        /// the current state and per-HTLC limit(s). This is intended for use when routing, allowing us
        /// to use a limit as close as possible to the HTLC limit we can currently send.
        ///
-       /// See also [`ChannelDetails::balance_msat`] and [`ChannelDetails::outbound_capacity_msat`].
+       /// See also [`ChannelDetails::next_outbound_htlc_minimum_msat`],
+       /// [`ChannelDetails::balance_msat`], and [`ChannelDetails::outbound_capacity_msat`].
        pub next_outbound_htlc_limit_msat: u64,
+       /// The minimum value for sending a single HTLC to the remote peer. This is the equivalent of
+       /// [`ChannelDetails::next_outbound_htlc_limit_msat`] but represents a lower-bound, rather than
+       /// an upper-bound. This is intended for use when routing, allowing us to ensure we pick a
+       /// route which is valid.
+       pub next_outbound_htlc_minimum_msat: u64,
        /// The available inbound capacity for the remote peer to send HTLCs to us. This does not
        /// include any pending HTLCs which are not yet fully resolved (and, thus, whose balance is not
        /// available for inclusion in new inbound HTLCs).
@@ -1249,53 +1495,54 @@ impl ChannelDetails {
                self.short_channel_id.or(self.outbound_scid_alias)
        }
 
-       fn from_channel<Signer: WriteableEcdsaChannelSigner>(channel: &Channel<Signer>,
+       fn from_channel_context<Signer: WriteableEcdsaChannelSigner>(context: &ChannelContext<Signer>,
                best_block_height: u32, latest_features: InitFeatures) -> Self {
 
-               let balance = channel.get_available_balances();
+               let balance = context.get_available_balances();
                let (to_remote_reserve_satoshis, to_self_reserve_satoshis) =
-                       channel.get_holder_counterparty_selected_channel_reserve_satoshis();
+                       context.get_holder_counterparty_selected_channel_reserve_satoshis();
                ChannelDetails {
-                       channel_id: channel.channel_id(),
+                       channel_id: context.channel_id(),
                        counterparty: ChannelCounterparty {
-                               node_id: channel.get_counterparty_node_id(),
+                               node_id: context.get_counterparty_node_id(),
                                features: latest_features,
                                unspendable_punishment_reserve: to_remote_reserve_satoshis,
-                               forwarding_info: channel.counterparty_forwarding_info(),
+                               forwarding_info: context.counterparty_forwarding_info(),
                                // Ensures that we have actually received the `htlc_minimum_msat` value
                                // from the counterparty through the `OpenChannel` or `AcceptChannel`
                                // message (as they are always the first message from the counterparty).
                                // Else `Channel::get_counterparty_htlc_minimum_msat` could return the
                                // default `0` value set by `Channel::new_outbound`.
-                               outbound_htlc_minimum_msat: if channel.have_received_message() {
-                                       Some(channel.get_counterparty_htlc_minimum_msat()) } else { None },
-                               outbound_htlc_maximum_msat: channel.get_counterparty_htlc_maximum_msat(),
+                               outbound_htlc_minimum_msat: if context.have_received_message() {
+                                       Some(context.get_counterparty_htlc_minimum_msat()) } else { None },
+                               outbound_htlc_maximum_msat: context.get_counterparty_htlc_maximum_msat(),
                        },
-                       funding_txo: channel.get_funding_txo(),
+                       funding_txo: context.get_funding_txo(),
                        // Note that accept_channel (or open_channel) is always the first message, so
                        // `have_received_message` indicates that type negotiation has completed.
-                       channel_type: if channel.have_received_message() { Some(channel.get_channel_type().clone()) } else { None },
-                       short_channel_id: channel.get_short_channel_id(),
-                       outbound_scid_alias: if channel.is_usable() { Some(channel.outbound_scid_alias()) } else { None },
-                       inbound_scid_alias: channel.latest_inbound_scid_alias(),
-                       channel_value_satoshis: channel.get_value_satoshis(),
-                       feerate_sat_per_1000_weight: Some(channel.get_feerate_sat_per_1000_weight()),
+                       channel_type: if context.have_received_message() { Some(context.get_channel_type().clone()) } else { None },
+                       short_channel_id: context.get_short_channel_id(),
+                       outbound_scid_alias: if context.is_usable() { Some(context.outbound_scid_alias()) } else { None },
+                       inbound_scid_alias: context.latest_inbound_scid_alias(),
+                       channel_value_satoshis: context.get_value_satoshis(),
+                       feerate_sat_per_1000_weight: Some(context.get_feerate_sat_per_1000_weight()),
                        unspendable_punishment_reserve: to_self_reserve_satoshis,
                        balance_msat: balance.balance_msat,
                        inbound_capacity_msat: balance.inbound_capacity_msat,
                        outbound_capacity_msat: balance.outbound_capacity_msat,
                        next_outbound_htlc_limit_msat: balance.next_outbound_htlc_limit_msat,
-                       user_channel_id: channel.get_user_id(),
-                       confirmations_required: channel.minimum_depth(),
-                       confirmations: Some(channel.get_funding_tx_confirmations(best_block_height)),
-                       force_close_spend_delay: channel.get_counterparty_selected_contest_delay(),
-                       is_outbound: channel.is_outbound(),
-                       is_channel_ready: channel.is_usable(),
-                       is_usable: channel.is_live(),
-                       is_public: channel.should_announce(),
-                       inbound_htlc_minimum_msat: Some(channel.get_holder_htlc_minimum_msat()),
-                       inbound_htlc_maximum_msat: channel.get_holder_htlc_maximum_msat(),
-                       config: Some(channel.config()),
+                       next_outbound_htlc_minimum_msat: balance.next_outbound_htlc_minimum_msat,
+                       user_channel_id: context.get_user_id(),
+                       confirmations_required: context.minimum_depth(),
+                       confirmations: Some(context.get_funding_tx_confirmations(best_block_height)),
+                       force_close_spend_delay: context.get_counterparty_selected_contest_delay(),
+                       is_outbound: context.is_outbound(),
+                       is_channel_ready: context.is_usable(),
+                       is_usable: context.is_live(),
+                       is_public: context.should_announce(),
+                       inbound_htlc_minimum_msat: Some(context.get_holder_htlc_minimum_msat()),
+                       inbound_htlc_maximum_msat: context.get_holder_htlc_maximum_msat(),
+                       config: Some(context.config()),
                }
        }
 }
@@ -1332,7 +1579,7 @@ pub enum RecentPaymentDetails {
 
 /// Route hints used in constructing invoices for [phantom node payents].
 ///
-/// [phantom node payments]: crate::chain::keysinterface::PhantomKeysManager
+/// [phantom node payments]: crate::sign::PhantomKeysManager
 #[derive(Clone)]
 pub struct PhantomRouteHints {
        /// The list of channels to be included in the invoice route hints.
@@ -1345,15 +1592,15 @@ pub struct PhantomRouteHints {
 }
 
 macro_rules! handle_error {
-       ($self: ident, $internal: expr, $counterparty_node_id: expr) => {
+       ($self: ident, $internal: expr, $counterparty_node_id: expr) => { {
+               // In testing, ensure there are no deadlocks where the lock is already held upon
+               // entering the macro.
+               debug_assert_ne!($self.pending_events.held_by_thread(), LockHeldState::HeldByThread);
+               debug_assert_ne!($self.per_peer_state.held_by_thread(), LockHeldState::HeldByThread);
+
                match $internal {
                        Ok(msg) => Ok(msg),
                        Err(MsgHandleErrInternal { err, chan_id, shutdown_finish }) => {
-                               // In testing, ensure there are no deadlocks where the lock is already held upon
-                               // entering the macro.
-                               debug_assert_ne!($self.pending_events.held_by_thread(), LockHeldState::HeldByThread);
-                               debug_assert_ne!($self.per_peer_state.held_by_thread(), LockHeldState::HeldByThread);
-
                                let mut msg_events = Vec::with_capacity(2);
 
                                if let Some((shutdown_res, update_option)) = shutdown_finish {
@@ -1364,10 +1611,10 @@ macro_rules! handle_error {
                                                });
                                        }
                                        if let Some((channel_id, user_channel_id)) = chan_id {
-                                               $self.pending_events.lock().unwrap().push(events::Event::ChannelClosed {
+                                               $self.pending_events.lock().unwrap().push_back((events::Event::ChannelClosed {
                                                        channel_id, user_channel_id,
                                                        reason: ClosureReason::ProcessingError { err: err.err.clone() }
-                                               });
+                                               }, None));
                                        }
                                }
 
@@ -1392,14 +1639,23 @@ macro_rules! handle_error {
                                Err(err)
                        },
                }
-       }
+       } };
+       ($self: ident, $internal: expr) => {
+               match $internal {
+                       Ok(res) => Ok(res),
+                       Err((chan, msg_handle_err)) => {
+                               let counterparty_node_id = chan.get_counterparty_node_id();
+                               handle_error!($self, Err(msg_handle_err), counterparty_node_id).map_err(|err| (chan, err))
+                       },
+               }
+       };
 }
 
 macro_rules! update_maps_on_chan_removal {
-       ($self: expr, $channel: expr) => {{
-               $self.id_to_peer.lock().unwrap().remove(&$channel.channel_id());
+       ($self: expr, $channel_context: expr) => {{
+               $self.id_to_peer.lock().unwrap().remove(&$channel_context.channel_id());
                let mut short_to_chan_info = $self.short_to_chan_info.write().unwrap();
-               if let Some(short_id) = $channel.get_short_channel_id() {
+               if let Some(short_id) = $channel_context.get_short_channel_id() {
                        short_to_chan_info.remove(&short_id);
                } else {
                        // If the channel was never confirmed on-chain prior to its closure, remove the
@@ -1408,10 +1664,10 @@ macro_rules! update_maps_on_chan_removal {
                        // also don't want a counterparty to be able to trivially cause a memory leak by simply
                        // opening a million channels with us which are closed before we ever reach the funding
                        // stage.
-                       let alias_removed = $self.outbound_scid_aliases.lock().unwrap().remove(&$channel.outbound_scid_alias());
+                       let alias_removed = $self.outbound_scid_aliases.lock().unwrap().remove(&$channel_context.outbound_scid_alias());
                        debug_assert!(alias_removed);
                }
-               short_to_chan_info.remove(&$channel.outbound_scid_alias());
+               short_to_chan_info.remove(&$channel_context.outbound_scid_alias());
        }}
 }
 
@@ -1427,12 +1683,25 @@ macro_rules! convert_chan_err {
                        },
                        ChannelError::Close(msg) => {
                                log_error!($self.logger, "Closing channel {} due to close-required error: {}", log_bytes!($channel_id[..]), msg);
-                               update_maps_on_chan_removal!($self, $channel);
-                               let shutdown_res = $channel.force_shutdown(true);
-                               (true, MsgHandleErrInternal::from_finish_shutdown(msg, *$channel_id, $channel.get_user_id(),
+                               update_maps_on_chan_removal!($self, &$channel.context);
+                               let shutdown_res = $channel.context.force_shutdown(true);
+                               (true, MsgHandleErrInternal::from_finish_shutdown(msg, *$channel_id, $channel.context.get_user_id(),
                                        shutdown_res, $self.get_channel_update_for_broadcast(&$channel).ok()))
                        },
                }
+       };
+       ($self: ident, $err: expr, $channel_context: expr, $channel_id: expr, PREFUNDED) => {
+               match $err {
+                       // We should only ever have `ChannelError::Close` when prefunded channels error.
+                       // In any case, just close the channel.
+                       ChannelError::Warn(msg) | ChannelError::Ignore(msg) | ChannelError::Close(msg) => {
+                               log_error!($self.logger, "Closing prefunded channel {} due to an error: {}", log_bytes!($channel_id[..]), msg);
+                               update_maps_on_chan_removal!($self, &$channel_context);
+                               let shutdown_res = $channel_context.force_shutdown(false);
+                               (true, MsgHandleErrInternal::from_finish_shutdown(msg, *$channel_id, $channel_context.get_user_id(),
+                                       shutdown_res, None))
+                       },
+               }
        }
 }
 
@@ -1451,6 +1720,21 @@ macro_rules! break_chan_entry {
        }
 }
 
+macro_rules! try_v1_outbound_chan_entry {
+       ($self: ident, $res: expr, $entry: expr) => {
+               match $res {
+                       Ok(res) => res,
+                       Err(e) => {
+                               let (drop, res) = convert_chan_err!($self, e, $entry.get_mut().context, $entry.key(), PREFUNDED);
+                               if drop {
+                                       $entry.remove_entry();
+                               }
+                               return Err(res);
+                       }
+               }
+       }
+}
+
 macro_rules! try_chan_entry {
        ($self: ident, $res: expr, $entry: expr) => {
                match $res {
@@ -1470,7 +1754,7 @@ macro_rules! remove_channel {
        ($self: expr, $entry: expr) => {
                {
                        let channel = $entry.remove_entry().1;
-                       update_maps_on_chan_removal!($self, channel);
+                       update_maps_on_chan_removal!($self, &channel.context);
                        channel
                }
        }
@@ -1479,36 +1763,49 @@ macro_rules! remove_channel {
 macro_rules! send_channel_ready {
        ($self: ident, $pending_msg_events: expr, $channel: expr, $channel_ready_msg: expr) => {{
                $pending_msg_events.push(events::MessageSendEvent::SendChannelReady {
-                       node_id: $channel.get_counterparty_node_id(),
+                       node_id: $channel.context.get_counterparty_node_id(),
                        msg: $channel_ready_msg,
                });
                // Note that we may send a `channel_ready` multiple times for a channel if we reconnect, so
                // we allow collisions, but we shouldn't ever be updating the channel ID pointed to.
                let mut short_to_chan_info = $self.short_to_chan_info.write().unwrap();
-               let outbound_alias_insert = short_to_chan_info.insert($channel.outbound_scid_alias(), ($channel.get_counterparty_node_id(), $channel.channel_id()));
-               assert!(outbound_alias_insert.is_none() || outbound_alias_insert.unwrap() == ($channel.get_counterparty_node_id(), $channel.channel_id()),
+               let outbound_alias_insert = short_to_chan_info.insert($channel.context.outbound_scid_alias(), ($channel.context.get_counterparty_node_id(), $channel.context.channel_id()));
+               assert!(outbound_alias_insert.is_none() || outbound_alias_insert.unwrap() == ($channel.context.get_counterparty_node_id(), $channel.context.channel_id()),
                        "SCIDs should never collide - ensure you weren't behind the chain tip by a full month when creating channels");
-               if let Some(real_scid) = $channel.get_short_channel_id() {
-                       let scid_insert = short_to_chan_info.insert(real_scid, ($channel.get_counterparty_node_id(), $channel.channel_id()));
-                       assert!(scid_insert.is_none() || scid_insert.unwrap() == ($channel.get_counterparty_node_id(), $channel.channel_id()),
+               if let Some(real_scid) = $channel.context.get_short_channel_id() {
+                       let scid_insert = short_to_chan_info.insert(real_scid, ($channel.context.get_counterparty_node_id(), $channel.context.channel_id()));
+                       assert!(scid_insert.is_none() || scid_insert.unwrap() == ($channel.context.get_counterparty_node_id(), $channel.context.channel_id()),
                                "SCIDs should never collide - ensure you weren't behind the chain tip by a full month when creating channels");
                }
        }}
 }
 
+macro_rules! emit_channel_pending_event {
+       ($locked_events: expr, $channel: expr) => {
+               if $channel.context.should_emit_channel_pending_event() {
+                       $locked_events.push_back((events::Event::ChannelPending {
+                               channel_id: $channel.context.channel_id(),
+                               former_temporary_channel_id: $channel.context.temporary_channel_id(),
+                               counterparty_node_id: $channel.context.get_counterparty_node_id(),
+                               user_channel_id: $channel.context.get_user_id(),
+                               funding_txo: $channel.context.get_funding_txo().unwrap().into_bitcoin_outpoint(),
+                       }, None));
+                       $channel.context.set_channel_pending_event_emitted();
+               }
+       }
+}
+
 macro_rules! emit_channel_ready_event {
-       ($self: expr, $channel: expr) => {
-               if $channel.should_emit_channel_ready_event() {
-                       {
-                               let mut pending_events = $self.pending_events.lock().unwrap();
-                               pending_events.push(events::Event::ChannelReady {
-                                       channel_id: $channel.channel_id(),
-                                       user_channel_id: $channel.get_user_id(),
-                                       counterparty_node_id: $channel.get_counterparty_node_id(),
-                                       channel_type: $channel.get_channel_type().clone(),
-                               });
-                       }
-                       $channel.set_channel_ready_event_emitted();
+       ($locked_events: expr, $channel: expr) => {
+               if $channel.context.should_emit_channel_ready_event() {
+                       debug_assert!($channel.context.channel_pending_event_emitted());
+                       $locked_events.push_back((events::Event::ChannelReady {
+                               channel_id: $channel.context.channel_id(),
+                               user_channel_id: $channel.context.get_user_id(),
+                               counterparty_node_id: $channel.context.get_counterparty_node_id(),
+                               channel_type: $channel.context.get_channel_type().clone(),
+                       }, None));
+                       $channel.context.set_channel_ready_event_emitted();
                }
        }
 }
@@ -1518,8 +1815,8 @@ macro_rules! handle_monitor_update_completion {
                let mut updates = $chan.monitor_updating_restored(&$self.logger,
                        &$self.node_signer, $self.genesis_hash, &$self.default_configuration,
                        $self.best_block.read().unwrap().height());
-               let counterparty_node_id = $chan.get_counterparty_node_id();
-               let channel_update = if updates.channel_ready.is_some() && $chan.is_usable() {
+               let counterparty_node_id = $chan.context.get_counterparty_node_id();
+               let channel_update = if updates.channel_ready.is_some() && $chan.context.is_usable() {
                        // We only send a channel_update in the case where we are just now sending a
                        // channel_ready and the channel is in a usable state. We may re-send a
                        // channel_update later through the announcement_signatures process for public
@@ -1534,7 +1831,7 @@ macro_rules! handle_monitor_update_completion {
                } else { None };
 
                let update_actions = $peer_state.monitor_update_blocked_actions
-                       .remove(&$chan.channel_id()).unwrap_or(Vec::new());
+                       .remove(&$chan.context.channel_id()).unwrap_or(Vec::new());
 
                let htlc_forwards = $self.handle_channel_resumption(
                        &mut $peer_state.pending_msg_events, $chan, updates.raa,
@@ -1545,7 +1842,7 @@ macro_rules! handle_monitor_update_completion {
                        $peer_state.pending_msg_events.push(upd);
                }
 
-               let channel_id = $chan.channel_id();
+               let channel_id = $chan.context.channel_id();
                core::mem::drop($peer_state_lock);
                core::mem::drop($per_peer_state_lock);
 
@@ -1566,30 +1863,30 @@ macro_rules! handle_new_monitor_update {
        ($self: ident, $update_res: expr, $update_id: expr, $peer_state_lock: expr, $peer_state: expr, $per_peer_state_lock: expr, $chan: expr, MANUALLY_REMOVING, $remove: expr) => { {
                // update_maps_on_chan_removal needs to be able to take id_to_peer, so make sure we can in
                // any case so that it won't deadlock.
-               debug_assert!($self.id_to_peer.try_lock().is_ok());
+               debug_assert_ne!($self.id_to_peer.held_by_thread(), LockHeldState::HeldByThread);
+               #[cfg(debug_assertions)] {
+                       debug_assert!($self.background_events_processed_since_startup.load(Ordering::Acquire));
+               }
                match $update_res {
                        ChannelMonitorUpdateStatus::InProgress => {
                                log_debug!($self.logger, "ChannelMonitor update for {} in flight, holding messages until the update completes.",
-                                       log_bytes!($chan.channel_id()[..]));
+                                       log_bytes!($chan.context.channel_id()[..]));
                                Ok(())
                        },
                        ChannelMonitorUpdateStatus::PermanentFailure => {
                                log_error!($self.logger, "Closing channel {} due to monitor update ChannelMonitorUpdateStatus::PermanentFailure",
-                                       log_bytes!($chan.channel_id()[..]));
-                               update_maps_on_chan_removal!($self, $chan);
+                                       log_bytes!($chan.context.channel_id()[..]));
+                               update_maps_on_chan_removal!($self, &$chan.context);
                                let res: Result<(), _> = Err(MsgHandleErrInternal::from_finish_shutdown(
-                                       "ChannelMonitor storage failure".to_owned(), $chan.channel_id(),
-                                       $chan.get_user_id(), $chan.force_shutdown(false),
+                                       "ChannelMonitor storage failure".to_owned(), $chan.context.channel_id(),
+                                       $chan.context.get_user_id(), $chan.context.force_shutdown(false),
                                        $self.get_channel_update_for_broadcast(&$chan).ok()));
                                $remove;
                                res
                        },
                        ChannelMonitorUpdateStatus::Completed => {
-                               if ($update_id == 0 || $chan.get_next_monitor_update()
-                                       .expect("We can't be processing a monitor update if it isn't queued")
-                                       .update_id == $update_id) &&
-                                       $chan.get_latest_monitor_update_id() == $update_id
-                               {
+                               $chan.complete_one_mon_update($update_id);
+                               if $chan.no_monitor_updates_pending() {
                                        handle_monitor_update_completion!($self, $update_id, $peer_state_lock, $peer_state, $per_peer_state_lock, $chan);
                                }
                                Ok(())
@@ -1601,6 +1898,68 @@ macro_rules! handle_new_monitor_update {
        }
 }
 
+macro_rules! process_events_body {
+       ($self: expr, $event_to_handle: expr, $handle_event: expr) => {
+               let mut processed_all_events = false;
+               while !processed_all_events {
+                       if $self.pending_events_processor.compare_exchange(false, true, Ordering::Acquire, Ordering::Relaxed).is_err() {
+                               return;
+                       }
+
+                       let mut result = NotifyOption::SkipPersist;
+
+                       {
+                               // We'll acquire our total consistency lock so that we can be sure no other
+                               // persists happen while processing monitor events.
+                               let _read_guard = $self.total_consistency_lock.read().unwrap();
+
+                               // Because `handle_post_event_actions` may send `ChannelMonitorUpdate`s to the user we must
+                               // ensure any startup-generated background events are handled first.
+                               if $self.process_background_events() == NotifyOption::DoPersist { result = NotifyOption::DoPersist; }
+
+                               // TODO: This behavior should be documented. It's unintuitive that we query
+                               // ChannelMonitors when clearing other events.
+                               if $self.process_pending_monitor_events() {
+                                       result = NotifyOption::DoPersist;
+                               }
+                       }
+
+                       let pending_events = $self.pending_events.lock().unwrap().clone();
+                       let num_events = pending_events.len();
+                       if !pending_events.is_empty() {
+                               result = NotifyOption::DoPersist;
+                       }
+
+                       let mut post_event_actions = Vec::new();
+
+                       for (event, action_opt) in pending_events {
+                               $event_to_handle = event;
+                               $handle_event;
+                               if let Some(action) = action_opt {
+                                       post_event_actions.push(action);
+                               }
+                       }
+
+                       {
+                               let mut pending_events = $self.pending_events.lock().unwrap();
+                               pending_events.drain(..num_events);
+                               processed_all_events = pending_events.is_empty();
+                               $self.pending_events_processor.store(false, Ordering::Release);
+                       }
+
+                       if !post_event_actions.is_empty() {
+                               $self.handle_post_event_actions(post_event_actions);
+                               // If we had some actions, go around again as we may have more events now
+                               processed_all_events = false;
+                       }
+
+                       if result == NotifyOption::DoPersist {
+                               $self.persistence_notifier.notify();
+                       }
+               }
+       }
+}
+
 impl<M: Deref, T: Deref, ES: Deref, NS: Deref, SP: Deref, F: Deref, R: Deref, L: Deref> ChannelManager<M, T, ES, NS, SP, F, R, L>
 where
        M::Target: chain::Watch<<SP::Target as SignerProvider>::Signer>,
@@ -1646,7 +2005,7 @@ where
                        pending_inbound_payments: Mutex::new(HashMap::new()),
                        pending_outbound_payments: OutboundPayments::new(),
                        forward_htlcs: Mutex::new(HashMap::new()),
-                       claimable_payments: Mutex::new(ClaimablePayments { claimable_htlcs: HashMap::new(), pending_claiming_payments: HashMap::new() }),
+                       claimable_payments: Mutex::new(ClaimablePayments { claimable_payments: HashMap::new(), pending_claiming_payments: HashMap::new() }),
                        pending_intercepted_htlcs: Mutex::new(HashMap::new()),
                        id_to_peer: Mutex::new(HashMap::new()),
                        short_to_chan_info: FairRwLock::new(HashMap::new()),
@@ -1663,9 +2022,12 @@ where
 
                        per_peer_state: FairRwLock::new(HashMap::new()),
 
-                       pending_events: Mutex::new(Vec::new()),
+                       pending_events: Mutex::new(VecDeque::new()),
+                       pending_events_processor: AtomicBool::new(false),
                        pending_background_events: Mutex::new(Vec::new()),
                        total_consistency_lock: RwLock::new(()),
+                       #[cfg(debug_assertions)]
+                       background_events_processed_since_startup: AtomicBool::new(false),
                        persistence_notifier: Notifier::new(),
 
                        entropy_source,
@@ -1711,6 +2073,10 @@ where
        /// Raises [`APIError::APIMisuseError`] when `channel_value_satoshis` > 2**24 or `push_msat` is
        /// greater than `channel_value_satoshis * 1k` or `channel_value_satoshis < 1000`.
        ///
+       /// Raises [`APIError::ChannelUnavailable`] if the channel cannot be opened due to failing to
+       /// generate a shutdown scriptpubkey or destination script set by
+       /// [`SignerProvider::get_shutdown_scriptpubkey`] or [`SignerProvider::get_destination_script`].
+       ///
        /// Note that we do not check if you are currently connected to the given peer. If no
        /// connection is available, the outbound `open_channel` message may fail to send, resulting in
        /// the channel eventually being silently forgotten (dropped on reload).
@@ -1730,7 +2096,7 @@ where
                        return Err(APIError::APIMisuseError { err: format!("Channel value must be at least 1000 satoshis. It was {}", channel_value_satoshis) });
                }
 
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
                // We want to make sure the lock is actually acquired by PersistenceNotifierGuard.
                debug_assert!(&self.total_consistency_lock.try_write().is_err());
 
@@ -1744,7 +2110,7 @@ where
                        let outbound_scid_alias = self.create_and_insert_outbound_scid_alias();
                        let their_features = &peer_state.latest_features;
                        let config = if override_config.is_some() { override_config.as_ref().unwrap() } else { &self.default_configuration };
-                       match Channel::new_outbound(&self.fee_estimator, &self.entropy_source, &self.signer_provider, their_network_key,
+                       match OutboundV1Channel::new(&self.fee_estimator, &self.entropy_source, &self.signer_provider, their_network_key,
                                their_features, channel_value_satoshis, push_msat, user_channel_id, config,
                                self.best_block.read().unwrap().height(), outbound_scid_alias)
                        {
@@ -1757,8 +2123,8 @@ where
                };
                let res = channel.get_open_channel(self.genesis_hash.clone());
 
-               let temporary_channel_id = channel.channel_id();
-               match peer_state.channel_by_id.entry(temporary_channel_id) {
+               let temporary_channel_id = channel.context.channel_id();
+               match peer_state.outbound_v1_channel_by_id.entry(temporary_channel_id) {
                        hash_map::Entry::Occupied(_) => {
                                if cfg!(fuzzing) {
                                        return Err(APIError::APIMisuseError { err: "Fuzzy bad RNG".to_owned() });
@@ -1776,7 +2142,7 @@ where
                Ok(temporary_channel_id)
        }
 
-       fn list_channels_with_filter<Fn: FnMut(&(&[u8; 32], &Channel<<SP::Target as SignerProvider>::Signer>)) -> bool + Copy>(&self, f: Fn) -> Vec<ChannelDetails> {
+       fn list_funded_channels_with_filter<Fn: FnMut(&(&[u8; 32], &Channel<<SP::Target as SignerProvider>::Signer>)) -> bool + Copy>(&self, f: Fn) -> Vec<ChannelDetails> {
                // Allocate our best estimate of the number of channels we have in the `res`
                // Vec. Sadly the `short_to_chan_info` map doesn't cover channels without
                // a scid or a scid alias, and the `id_to_peer` shouldn't be used outside
@@ -1791,7 +2157,7 @@ where
                                let mut peer_state_lock = peer_state_mutex.lock().unwrap();
                                let peer_state = &mut *peer_state_lock;
                                for (_channel_id, channel) in peer_state.channel_by_id.iter().filter(f) {
-                                       let details = ChannelDetails::from_channel(channel, best_block_height,
+                                       let details = ChannelDetails::from_channel_context(&channel.context, best_block_height,
                                                peer_state.latest_features.clone());
                                        res.push(details);
                                }
@@ -1803,7 +2169,37 @@ where
        /// Gets the list of open channels, in random order. See [`ChannelDetails`] field documentation for
        /// more information.
        pub fn list_channels(&self) -> Vec<ChannelDetails> {
-               self.list_channels_with_filter(|_| true)
+               // Allocate our best estimate of the number of channels we have in the `res`
+               // Vec. Sadly the `short_to_chan_info` map doesn't cover channels without
+               // a scid or a scid alias, and the `id_to_peer` shouldn't be used outside
+               // of the ChannelMonitor handling. Therefore reallocations may still occur, but is
+               // unlikely as the `short_to_chan_info` map often contains 2 entries for
+               // the same channel.
+               let mut res = Vec::with_capacity(self.short_to_chan_info.read().unwrap().len());
+               {
+                       let best_block_height = self.best_block.read().unwrap().height();
+                       let per_peer_state = self.per_peer_state.read().unwrap();
+                       for (_cp_id, peer_state_mutex) in per_peer_state.iter() {
+                               let mut peer_state_lock = peer_state_mutex.lock().unwrap();
+                               let peer_state = &mut *peer_state_lock;
+                               for (_channel_id, channel) in peer_state.channel_by_id.iter() {
+                                       let details = ChannelDetails::from_channel_context(&channel.context, best_block_height,
+                                               peer_state.latest_features.clone());
+                                       res.push(details);
+                               }
+                               for (_channel_id, channel) in peer_state.inbound_v1_channel_by_id.iter() {
+                                       let details = ChannelDetails::from_channel_context(&channel.context, best_block_height,
+                                               peer_state.latest_features.clone());
+                                       res.push(details);
+                               }
+                               for (_channel_id, channel) in peer_state.outbound_v1_channel_by_id.iter() {
+                                       let details = ChannelDetails::from_channel_context(&channel.context, best_block_height,
+                                               peer_state.latest_features.clone());
+                                       res.push(details);
+                               }
+                       }
+               }
+               res
        }
 
        /// Gets the list of usable channels, in random order. Useful as an argument to
@@ -1816,7 +2212,7 @@ where
                // Note we use is_live here instead of usable which leads to somewhat confused
                // internal/external nomenclature, but that's ok cause that's probably what the user
                // really wanted anyway.
-               self.list_channels_with_filter(|&(_, ref channel)| channel.is_live())
+               self.list_funded_channels_with_filter(|&(_, ref channel)| channel.context.is_live())
        }
 
        /// Gets the list of channels we have with a given counterparty, in random order.
@@ -1831,7 +2227,7 @@ where
                        return peer_state.channel_by_id
                                .iter()
                                .map(|(_, channel)|
-                                       ChannelDetails::from_channel(channel, best_block_height, features.clone()))
+                                       ChannelDetails::from_channel_context(&channel.context, best_block_height, features.clone()))
                                .collect();
                }
                vec![]
@@ -1866,23 +2262,25 @@ where
        }
 
        /// Helper function that issues the channel close events
-       fn issue_channel_close_events(&self, channel: &Channel<<SP::Target as SignerProvider>::Signer>, closure_reason: ClosureReason) {
+       fn issue_channel_close_events(&self, context: &ChannelContext<<SP::Target as SignerProvider>::Signer>, closure_reason: ClosureReason) {
                let mut pending_events_lock = self.pending_events.lock().unwrap();
-               match channel.unbroadcasted_funding() {
+               match context.unbroadcasted_funding() {
                        Some(transaction) => {
-                               pending_events_lock.push(events::Event::DiscardFunding { channel_id: channel.channel_id(), transaction })
+                               pending_events_lock.push_back((events::Event::DiscardFunding {
+                                       channel_id: context.channel_id(), transaction
+                               }, None));
                        },
                        None => {},
                }
-               pending_events_lock.push(events::Event::ChannelClosed {
-                       channel_id: channel.channel_id(),
-                       user_channel_id: channel.get_user_id(),
+               pending_events_lock.push_back((events::Event::ChannelClosed {
+                       channel_id: context.channel_id(),
+                       user_channel_id: context.get_user_id(),
                        reason: closure_reason
-               });
+               }, None));
        }
 
-       fn close_channel_internal(&self, channel_id: &[u8; 32], counterparty_node_id: &PublicKey, target_feerate_sats_per_1000_weight: Option<u32>) -> Result<(), APIError> {
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+       fn close_channel_internal(&self, channel_id: &[u8; 32], counterparty_node_id: &PublicKey, target_feerate_sats_per_1000_weight: Option<u32>, override_shutdown_script: Option<ShutdownScript>) -> Result<(), APIError> {
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
 
                let mut failed_htlcs: Vec<(HTLCSource, PaymentHash)>;
                let result: Result<(), _> = loop {
@@ -1895,10 +2293,10 @@ where
                        let peer_state = &mut *peer_state_lock;
                        match peer_state.channel_by_id.entry(channel_id.clone()) {
                                hash_map::Entry::Occupied(mut chan_entry) => {
-                                       let funding_txo_opt = chan_entry.get().get_funding_txo();
+                                       let funding_txo_opt = chan_entry.get().context.get_funding_txo();
                                        let their_features = &peer_state.latest_features;
                                        let (shutdown_msg, mut monitor_update_opt, htlcs) = chan_entry.get_mut()
-                                               .get_shutdown(&self.signer_provider, their_features, target_feerate_sats_per_1000_weight)?;
+                                               .get_shutdown(&self.signer_provider, their_features, target_feerate_sats_per_1000_weight, override_shutdown_script)?;
                                        failed_htlcs = htlcs;
 
                                        // We can send the `shutdown` message before updating the `ChannelMonitor`
@@ -1923,7 +2321,7 @@ where
                                                                msg: channel_update
                                                        });
                                                }
-                                               self.issue_channel_close_events(&channel, ClosureReason::HolderForceClosed);
+                                               self.issue_channel_close_events(&channel.context, ClosureReason::HolderForceClosed);
                                        }
                                        break Ok(());
                                },
@@ -1955,12 +2353,17 @@ where
        ///
        /// May generate a [`SendShutdown`] message event on success, which should be relayed.
        ///
+       /// Raises [`APIError::ChannelUnavailable`] if the channel cannot be closed due to failing to
+       /// generate a shutdown scriptpubkey or destination script set by
+       /// [`SignerProvider::get_shutdown_scriptpubkey`]. A force-closure may be needed to close the
+       /// channel.
+       ///
        /// [`ChannelConfig::force_close_avoidance_max_fee_satoshis`]: crate::util::config::ChannelConfig::force_close_avoidance_max_fee_satoshis
        /// [`Background`]: crate::chain::chaininterface::ConfirmationTarget::Background
        /// [`Normal`]: crate::chain::chaininterface::ConfirmationTarget::Normal
        /// [`SendShutdown`]: crate::events::MessageSendEvent::SendShutdown
        pub fn close_channel(&self, channel_id: &[u8; 32], counterparty_node_id: &PublicKey) -> Result<(), APIError> {
-               self.close_channel_internal(channel_id, counterparty_node_id, None)
+               self.close_channel_internal(channel_id, counterparty_node_id, None, None)
        }
 
        /// Begins the process of closing a channel. After this call (plus some timeout), no new HTLCs
@@ -1977,14 +2380,24 @@ where
        ///    transaction feerate below `target_feerate_sat_per_1000_weight` (or the feerate which
        ///    will appear on a force-closure transaction, whichever is lower).
        ///
+       /// The `shutdown_script` provided  will be used as the `scriptPubKey` for the closing transaction.
+       /// Will fail if a shutdown script has already been set for this channel by
+       /// ['ChannelHandshakeConfig::commit_upfront_shutdown_pubkey`]. The given shutdown script must
+       /// also be compatible with our and the counterparty's features.
+       ///
        /// May generate a [`SendShutdown`] message event on success, which should be relayed.
        ///
+       /// Raises [`APIError::ChannelUnavailable`] if the channel cannot be closed due to failing to
+       /// generate a shutdown scriptpubkey or destination script set by
+       /// [`SignerProvider::get_shutdown_scriptpubkey`]. A force-closure may be needed to close the
+       /// channel.
+       ///
        /// [`ChannelConfig::force_close_avoidance_max_fee_satoshis`]: crate::util::config::ChannelConfig::force_close_avoidance_max_fee_satoshis
        /// [`Background`]: crate::chain::chaininterface::ConfirmationTarget::Background
        /// [`Normal`]: crate::chain::chaininterface::ConfirmationTarget::Normal
        /// [`SendShutdown`]: crate::events::MessageSendEvent::SendShutdown
-       pub fn close_channel_with_target_feerate(&self, channel_id: &[u8; 32], counterparty_node_id: &PublicKey, target_feerate_sats_per_1000_weight: u32) -> Result<(), APIError> {
-               self.close_channel_internal(channel_id, counterparty_node_id, Some(target_feerate_sats_per_1000_weight))
+       pub fn close_channel_with_feerate_and_script(&self, channel_id: &[u8; 32], counterparty_node_id: &PublicKey, target_feerate_sats_per_1000_weight: Option<u32>, shutdown_script: Option<ShutdownScript>) -> Result<(), APIError> {
+               self.close_channel_internal(channel_id, counterparty_node_id, target_feerate_sats_per_1000_weight, shutdown_script)
        }
 
        #[inline]
@@ -1997,7 +2410,7 @@ where
                        let receiver = HTLCDestination::NextHopChannel { node_id: Some(counterparty_node_id), channel_id };
                        self.fail_htlc_backwards_internal(&source, &payment_hash, &reason, receiver);
                }
-               if let Some((funding_txo, monitor_update)) = monitor_update_option {
+               if let Some((_, funding_txo, monitor_update)) = monitor_update_option {
                        // There isn't anything we can do if we get an update failure - we're already
                        // force-closing. The monitor update on the required in-memory copy should broadcast
                        // the latest local state, which is the best we can do anyway. Thus, it is safe to
@@ -2013,34 +2426,50 @@ where
                let per_peer_state = self.per_peer_state.read().unwrap();
                let peer_state_mutex = per_peer_state.get(peer_node_id)
                        .ok_or_else(|| APIError::ChannelUnavailable { err: format!("Can't find a peer matching the passed counterparty node_id {}", peer_node_id) })?;
-               let mut chan = {
+               let (update_opt, counterparty_node_id) = {
                        let mut peer_state_lock = peer_state_mutex.lock().unwrap();
                        let peer_state = &mut *peer_state_lock;
+                       let closure_reason = if let Some(peer_msg) = peer_msg {
+                               ClosureReason::CounterpartyForceClosed { peer_msg: UntrustedString(peer_msg.to_string()) }
+                       } else {
+                               ClosureReason::HolderForceClosed
+                       };
                        if let hash_map::Entry::Occupied(chan) = peer_state.channel_by_id.entry(channel_id.clone()) {
-                               if let Some(peer_msg) = peer_msg {
-                                       self.issue_channel_close_events(chan.get(),ClosureReason::CounterpartyForceClosed { peer_msg: UntrustedString(peer_msg.to_string()) });
-                               } else {
-                                       self.issue_channel_close_events(chan.get(),ClosureReason::HolderForceClosed);
-                               }
-                               remove_channel!(self, chan)
+                               log_error!(self.logger, "Force-closing channel {}", log_bytes!(channel_id[..]));
+                               self.issue_channel_close_events(&chan.get().context, closure_reason);
+                               let mut chan = remove_channel!(self, chan);
+                               self.finish_force_close_channel(chan.context.force_shutdown(broadcast));
+                               (self.get_channel_update_for_broadcast(&chan).ok(), chan.context.get_counterparty_node_id())
+                       } else if let hash_map::Entry::Occupied(chan) = peer_state.outbound_v1_channel_by_id.entry(channel_id.clone()) {
+                               log_error!(self.logger, "Force-closing channel {}", log_bytes!(channel_id[..]));
+                               self.issue_channel_close_events(&chan.get().context, closure_reason);
+                               let mut chan = remove_channel!(self, chan);
+                               self.finish_force_close_channel(chan.context.force_shutdown(false));
+                               // Prefunded channel has no update
+                               (None, chan.context.get_counterparty_node_id())
+                       } else if let hash_map::Entry::Occupied(chan) = peer_state.inbound_v1_channel_by_id.entry(channel_id.clone()) {
+                               log_error!(self.logger, "Force-closing channel {}", log_bytes!(channel_id[..]));
+                               self.issue_channel_close_events(&chan.get().context, closure_reason);
+                               let mut chan = remove_channel!(self, chan);
+                               self.finish_force_close_channel(chan.context.force_shutdown(false));
+                               // Prefunded channel has no update
+                               (None, chan.context.get_counterparty_node_id())
                        } else {
                                return Err(APIError::ChannelUnavailable{ err: format!("Channel with id {} not found for the passed counterparty node_id {}", log_bytes!(*channel_id), peer_node_id) });
                        }
                };
-               log_error!(self.logger, "Force-closing channel {}", log_bytes!(channel_id[..]));
-               self.finish_force_close_channel(chan.force_shutdown(broadcast));
-               if let Ok(update) = self.get_channel_update_for_broadcast(&chan) {
+               if let Some(update) = update_opt {
                        let mut peer_state = peer_state_mutex.lock().unwrap();
                        peer_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
                                msg: update
                        });
                }
 
-               Ok(chan.get_counterparty_node_id())
+               Ok(counterparty_node_id)
        }
 
        fn force_close_sending_error(&self, channel_id: &[u8; 32], counterparty_node_id: &PublicKey, broadcast: bool) -> Result<(), APIError> {
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
                match self.force_close_channel_with_peer(channel_id, counterparty_node_id, None, broadcast) {
                        Ok(counterparty_node_id) => {
                                let per_peer_state = self.per_peer_state.read().unwrap();
@@ -2141,20 +2570,8 @@ where
                                        msg: "Got non final data with an HMAC of 0",
                                });
                        },
-                       msgs::OnionHopDataFormat::FinalNode { payment_data, keysend_preimage } => {
-                               if payment_data.is_some() && keysend_preimage.is_some() {
-                                       return Err(ReceiveError {
-                                               err_code: 0x4000|22,
-                                               err_data: Vec::new(),
-                                               msg: "We don't support MPP keysend payments",
-                                       });
-                               } else if let Some(data) = payment_data {
-                                       PendingHTLCRouting::Receive {
-                                               payment_data: data,
-                                               incoming_cltv_expiry: hop_data.outgoing_cltv_value,
-                                               phantom_shared_secret,
-                                       }
-                               } else if let Some(payment_preimage) = keysend_preimage {
+                       msgs::OnionHopDataFormat::FinalNode { payment_data, keysend_preimage, payment_metadata } => {
+                               if let Some(payment_preimage) = keysend_preimage {
                                        // We need to check that the sender knows the keysend preimage before processing this
                                        // payment further. Otherwise, an intermediary routing hop forwarding non-keysend-HTLC X
                                        // could discover the final destination of X, by probing the adjacent nodes on the route
@@ -2168,10 +2585,25 @@ where
                                                        msg: "Payment preimage didn't match payment hash",
                                                });
                                        }
-
+                                       if !self.default_configuration.accept_mpp_keysend && payment_data.is_some() {
+                                               return Err(ReceiveError {
+                                                       err_code: 0x4000|22,
+                                                       err_data: Vec::new(),
+                                                       msg: "We don't support MPP keysend payments",
+                                               });
+                                       }
                                        PendingHTLCRouting::ReceiveKeysend {
+                                               payment_data,
                                                payment_preimage,
+                                               payment_metadata,
+                                               incoming_cltv_expiry: hop_data.outgoing_cltv_value,
+                                       }
+                               } else if let Some(data) = payment_data {
+                                       PendingHTLCRouting::Receive {
+                                               payment_data: data,
+                                               payment_metadata,
                                                incoming_cltv_expiry: hop_data.outgoing_cltv_value,
+                                               phantom_shared_secret,
                                        }
                                } else {
                                        return Err(ReceiveError {
@@ -2189,15 +2621,18 @@ where
                        incoming_amt_msat: Some(amt_msat),
                        outgoing_amt_msat: hop_data.amt_to_forward,
                        outgoing_cltv_value: hop_data.outgoing_cltv_value,
+                       skimmed_fee_msat: None,
                })
        }
 
-       fn decode_update_add_htlc_onion(&self, msg: &msgs::UpdateAddHTLC) -> PendingHTLCStatus {
+       fn decode_update_add_htlc_onion(
+               &self, msg: &msgs::UpdateAddHTLC
+       ) -> Result<(onion_utils::Hop, [u8; 32], Option<Result<PublicKey, secp256k1::Error>>), HTLCFailureMsg> {
                macro_rules! return_malformed_err {
                        ($msg: expr, $err_code: expr) => {
                                {
                                        log_info!(self.logger, "Failed to accept/forward incoming HTLC: {}", $msg);
-                                       return PendingHTLCStatus::Fail(HTLCFailureMsg::Malformed(msgs::UpdateFailMalformedHTLC {
+                                       return Err(HTLCFailureMsg::Malformed(msgs::UpdateFailMalformedHTLC {
                                                channel_id: msg.channel_id,
                                                htlc_id: msg.htlc_id,
                                                sha256_of_onion: Sha256::hash(&msg.onion_routing_packet.hop_data).into_inner(),
@@ -2228,7 +2663,7 @@ where
                        ($msg: expr, $err_code: expr, $data: expr) => {
                                {
                                        log_info!(self.logger, "Failed to accept/forward incoming HTLC: {}", $msg);
-                                       return PendingHTLCStatus::Fail(HTLCFailureMsg::Relay(msgs::UpdateFailHTLC {
+                                       return Err(HTLCFailureMsg::Relay(msgs::UpdateFailHTLC {
                                                channel_id: msg.channel_id,
                                                htlc_id: msg.htlc_id,
                                                reason: HTLCFailReason::reason($err_code, $data.to_vec())
@@ -2247,8 +2682,181 @@ where
                                return_err!(err_msg, err_code, &[0; 0]);
                        },
                };
+               let (outgoing_scid, outgoing_amt_msat, outgoing_cltv_value, next_packet_pk_opt) = match next_hop {
+                       onion_utils::Hop::Forward {
+                               next_hop_data: msgs::OnionHopData {
+                                       format: msgs::OnionHopDataFormat::NonFinalNode { short_channel_id }, amt_to_forward,
+                                       outgoing_cltv_value,
+                               }, ..
+                       } => {
+                               let next_pk = onion_utils::next_hop_packet_pubkey(&self.secp_ctx,
+                                       msg.onion_routing_packet.public_key.unwrap(), &shared_secret);
+                               (short_channel_id, amt_to_forward, outgoing_cltv_value, Some(next_pk))
+                       },
+                       // We'll do receive checks in [`Self::construct_pending_htlc_info`] so we have access to the
+                       // inbound channel's state.
+                       onion_utils::Hop::Receive { .. } => return Ok((next_hop, shared_secret, None)),
+                       onion_utils::Hop::Forward {
+                               next_hop_data: msgs::OnionHopData { format: msgs::OnionHopDataFormat::FinalNode { .. }, .. }, ..
+                       } => {
+                               return_err!("Final Node OnionHopData provided for us as an intermediary node", 0x4000 | 22, &[0; 0]);
+                       }
+               };
+
+               // Perform outbound checks here instead of in [`Self::construct_pending_htlc_info`] because we
+               // can't hold the outbound peer state lock at the same time as the inbound peer state lock.
+               if let Some((err, mut code, chan_update)) = loop {
+                       let id_option = self.short_to_chan_info.read().unwrap().get(&outgoing_scid).cloned();
+                       let forwarding_chan_info_opt = match id_option {
+                               None => { // unknown_next_peer
+                                       // Note that this is likely a timing oracle for detecting whether an scid is a
+                                       // phantom or an intercept.
+                                       if (self.default_configuration.accept_intercept_htlcs &&
+                                               fake_scid::is_valid_intercept(&self.fake_scid_rand_bytes, outgoing_scid, &self.genesis_hash)) ||
+                                               fake_scid::is_valid_phantom(&self.fake_scid_rand_bytes, outgoing_scid, &self.genesis_hash)
+                                       {
+                                               None
+                                       } else {
+                                               break Some(("Don't have available channel for forwarding as requested.", 0x4000 | 10, None));
+                                       }
+                               },
+                               Some((cp_id, id)) => Some((cp_id.clone(), id.clone())),
+                       };
+                       let chan_update_opt = if let Some((counterparty_node_id, forwarding_id)) = forwarding_chan_info_opt {
+                               let per_peer_state = self.per_peer_state.read().unwrap();
+                               let peer_state_mutex_opt = per_peer_state.get(&counterparty_node_id);
+                               if peer_state_mutex_opt.is_none() {
+                                       break Some(("Don't have available channel for forwarding as requested.", 0x4000 | 10, None));
+                               }
+                               let mut peer_state_lock = peer_state_mutex_opt.unwrap().lock().unwrap();
+                               let peer_state = &mut *peer_state_lock;
+                               let chan = match peer_state.channel_by_id.get_mut(&forwarding_id) {
+                                       None => {
+                                               // Channel was removed. The short_to_chan_info and channel_by_id maps
+                                               // have no consistency guarantees.
+                                               break Some(("Don't have available channel for forwarding as requested.", 0x4000 | 10, None));
+                                       },
+                                       Some(chan) => chan
+                               };
+                               if !chan.context.should_announce() && !self.default_configuration.accept_forwards_to_priv_channels {
+                                       // Note that the behavior here should be identical to the above block - we
+                                       // should NOT reveal the existence or non-existence of a private channel if
+                                       // we don't allow forwards outbound over them.
+                                       break Some(("Refusing to forward to a private channel based on our config.", 0x4000 | 10, None));
+                               }
+                               if chan.context.get_channel_type().supports_scid_privacy() && outgoing_scid != chan.context.outbound_scid_alias() {
+                                       // `option_scid_alias` (referred to in LDK as `scid_privacy`) means
+                                       // "refuse to forward unless the SCID alias was used", so we pretend
+                                       // we don't have the channel here.
+                                       break Some(("Refusing to forward over real channel SCID as our counterparty requested.", 0x4000 | 10, None));
+                               }
+                               let chan_update_opt = self.get_channel_update_for_onion(outgoing_scid, chan).ok();
+
+                               // Note that we could technically not return an error yet here and just hope
+                               // that the connection is reestablished or monitor updated by the time we get
+                               // around to doing the actual forward, but better to fail early if we can and
+                               // hopefully an attacker trying to path-trace payments cannot make this occur
+                               // on a small/per-node/per-channel scale.
+                               if !chan.context.is_live() { // channel_disabled
+                                       // If the channel_update we're going to return is disabled (i.e. the
+                                       // peer has been disabled for some time), return `channel_disabled`,
+                                       // otherwise return `temporary_channel_failure`.
+                                       if chan_update_opt.as_ref().map(|u| u.contents.flags & 2 == 2).unwrap_or(false) {
+                                               break Some(("Forwarding channel has been disconnected for some time.", 0x1000 | 20, chan_update_opt));
+                                       } else {
+                                               break Some(("Forwarding channel is not in a ready state.", 0x1000 | 7, chan_update_opt));
+                                       }
+                               }
+                               if outgoing_amt_msat < chan.context.get_counterparty_htlc_minimum_msat() { // amount_below_minimum
+                                       break Some(("HTLC amount was below the htlc_minimum_msat", 0x1000 | 11, chan_update_opt));
+                               }
+                               if let Err((err, code)) = chan.htlc_satisfies_config(&msg, outgoing_amt_msat, outgoing_cltv_value) {
+                                       break Some((err, code, chan_update_opt));
+                               }
+                               chan_update_opt
+                       } else {
+                               if (msg.cltv_expiry as u64) < (outgoing_cltv_value) as u64 + MIN_CLTV_EXPIRY_DELTA as u64 {
+                                       // We really should set `incorrect_cltv_expiry` here but as we're not
+                                       // forwarding over a real channel we can't generate a channel_update
+                                       // for it. Instead we just return a generic temporary_node_failure.
+                                       break Some((
+                                                       "Forwarding node has tampered with the intended HTLC values or origin node has an obsolete cltv_expiry_delta",
+                                                       0x2000 | 2, None,
+                                       ));
+                               }
+                               None
+                       };
+
+                       let cur_height = self.best_block.read().unwrap().height() + 1;
+                       // Theoretically, channel counterparty shouldn't send us a HTLC expiring now,
+                       // but we want to be robust wrt to counterparty packet sanitization (see
+                       // HTLC_FAIL_BACK_BUFFER rationale).
+                       if msg.cltv_expiry <= cur_height + HTLC_FAIL_BACK_BUFFER as u32 { // expiry_too_soon
+                               break Some(("CLTV expiry is too close", 0x1000 | 14, chan_update_opt));
+                       }
+                       if msg.cltv_expiry > cur_height + CLTV_FAR_FAR_AWAY as u32 { // expiry_too_far
+                               break Some(("CLTV expiry is too far in the future", 21, None));
+                       }
+                       // If the HTLC expires ~now, don't bother trying to forward it to our
+                       // counterparty. They should fail it anyway, but we don't want to bother with
+                       // the round-trips or risk them deciding they definitely want the HTLC and
+                       // force-closing to ensure they get it if we're offline.
+                       // We previously had a much more aggressive check here which tried to ensure
+                       // our counterparty receives an HTLC which has *our* risk threshold met on it,
+                       // but there is no need to do that, and since we're a bit conservative with our
+                       // risk threshold it just results in failing to forward payments.
+                       if (outgoing_cltv_value) as u64 <= (cur_height + LATENCY_GRACE_PERIOD_BLOCKS) as u64 {
+                               break Some(("Outgoing CLTV value is too soon", 0x1000 | 14, chan_update_opt));
+                       }
+
+                       break None;
+               }
+               {
+                       let mut res = VecWriter(Vec::with_capacity(chan_update.serialized_length() + 2 + 8 + 2));
+                       if let Some(chan_update) = chan_update {
+                               if code == 0x1000 | 11 || code == 0x1000 | 12 {
+                                       msg.amount_msat.write(&mut res).expect("Writes cannot fail");
+                               }
+                               else if code == 0x1000 | 13 {
+                                       msg.cltv_expiry.write(&mut res).expect("Writes cannot fail");
+                               }
+                               else if code == 0x1000 | 20 {
+                                       // TODO: underspecified, follow https://github.com/lightning/bolts/issues/791
+                                       0u16.write(&mut res).expect("Writes cannot fail");
+                               }
+                               (chan_update.serialized_length() as u16 + 2).write(&mut res).expect("Writes cannot fail");
+                               msgs::ChannelUpdate::TYPE.write(&mut res).expect("Writes cannot fail");
+                               chan_update.write(&mut res).expect("Writes cannot fail");
+                       } else if code & 0x1000 == 0x1000 {
+                               // If we're trying to return an error that requires a `channel_update` but
+                               // we're forwarding to a phantom or intercept "channel" (i.e. cannot
+                               // generate an update), just use the generic "temporary_node_failure"
+                               // instead.
+                               code = 0x2000 | 2;
+                       }
+                       return_err!(err, code, &res.0[..]);
+               }
+               Ok((next_hop, shared_secret, next_packet_pk_opt))
+       }
 
-               let pending_forward_info = match next_hop {
+       fn construct_pending_htlc_status<'a>(
+               &self, msg: &msgs::UpdateAddHTLC, shared_secret: [u8; 32], decoded_hop: onion_utils::Hop,
+               next_packet_pubkey_opt: Option<Result<PublicKey, secp256k1::Error>>
+       ) -> PendingHTLCStatus {
+               macro_rules! return_err {
+                       ($msg: expr, $err_code: expr, $data: expr) => {
+                               {
+                                       log_info!(self.logger, "Failed to accept/forward incoming HTLC: {}", $msg);
+                                       return PendingHTLCStatus::Fail(HTLCFailureMsg::Relay(msgs::UpdateFailHTLC {
+                                               channel_id: msg.channel_id,
+                                               htlc_id: msg.htlc_id,
+                                               reason: HTLCFailReason::reason($err_code, $data.to_vec())
+                                                       .get_encrypted_failure_packet(&shared_secret, &None),
+                                       }));
+                               }
+                       }
+               }
+               match decoded_hop {
                        onion_utils::Hop::Receive(next_hop_data) => {
                                // OUR PAYMENT!
                                match self.construct_recv_pending_htlc_info(next_hop_data, shared_secret, msg.payment_hash, msg.amount_msat, msg.cltv_expiry, None) {
@@ -2263,10 +2871,10 @@ where
                                }
                        },
                        onion_utils::Hop::Forward { next_hop_data, next_hop_hmac, new_packet_bytes } => {
-                               let new_pubkey = msg.onion_routing_packet.public_key.unwrap();
+                               debug_assert!(next_packet_pubkey_opt.is_some());
                                let outgoing_packet = msgs::OnionPacket {
                                        version: 0,
-                                       public_key: onion_utils::next_hop_packet_pubkey(&self.secp_ctx, new_pubkey, &shared_secret),
+                                       public_key: next_packet_pubkey_opt.unwrap_or(Err(secp256k1::Error::InvalidPublicKey)),
                                        hop_data: new_packet_bytes,
                                        hmac: next_hop_hmac.clone(),
                                };
@@ -2288,143 +2896,10 @@ where
                                        incoming_amt_msat: Some(msg.amount_msat),
                                        outgoing_amt_msat: next_hop_data.amt_to_forward,
                                        outgoing_cltv_value: next_hop_data.outgoing_cltv_value,
+                                       skimmed_fee_msat: None,
                                })
                        }
-               };
-
-               if let &PendingHTLCStatus::Forward(PendingHTLCInfo { ref routing, ref outgoing_amt_msat, ref outgoing_cltv_value, .. }) = &pending_forward_info {
-                       // If short_channel_id is 0 here, we'll reject the HTLC as there cannot be a channel
-                       // with a short_channel_id of 0. This is important as various things later assume
-                       // short_channel_id is non-0 in any ::Forward.
-                       if let &PendingHTLCRouting::Forward { ref short_channel_id, .. } = routing {
-                               if let Some((err, mut code, chan_update)) = loop {
-                                       let id_option = self.short_to_chan_info.read().unwrap().get(short_channel_id).cloned();
-                                       let forwarding_chan_info_opt = match id_option {
-                                               None => { // unknown_next_peer
-                                                       // Note that this is likely a timing oracle for detecting whether an scid is a
-                                                       // phantom or an intercept.
-                                                       if (self.default_configuration.accept_intercept_htlcs &&
-                                                          fake_scid::is_valid_intercept(&self.fake_scid_rand_bytes, *short_channel_id, &self.genesis_hash)) ||
-                                                          fake_scid::is_valid_phantom(&self.fake_scid_rand_bytes, *short_channel_id, &self.genesis_hash)
-                                                       {
-                                                               None
-                                                       } else {
-                                                               break Some(("Don't have available channel for forwarding as requested.", 0x4000 | 10, None));
-                                                       }
-                                               },
-                                               Some((cp_id, id)) => Some((cp_id.clone(), id.clone())),
-                                       };
-                                       let chan_update_opt = if let Some((counterparty_node_id, forwarding_id)) = forwarding_chan_info_opt {
-                                               let per_peer_state = self.per_peer_state.read().unwrap();
-                                               let peer_state_mutex_opt = per_peer_state.get(&counterparty_node_id);
-                                               if peer_state_mutex_opt.is_none() {
-                                                       break Some(("Don't have available channel for forwarding as requested.", 0x4000 | 10, None));
-                                               }
-                                               let mut peer_state_lock = peer_state_mutex_opt.unwrap().lock().unwrap();
-                                               let peer_state = &mut *peer_state_lock;
-                                               let chan = match peer_state.channel_by_id.get_mut(&forwarding_id) {
-                                                       None => {
-                                                               // Channel was removed. The short_to_chan_info and channel_by_id maps
-                                                               // have no consistency guarantees.
-                                                               break Some(("Don't have available channel for forwarding as requested.", 0x4000 | 10, None));
-                                                       },
-                                                       Some(chan) => chan
-                                               };
-                                               if !chan.should_announce() && !self.default_configuration.accept_forwards_to_priv_channels {
-                                                       // Note that the behavior here should be identical to the above block - we
-                                                       // should NOT reveal the existence or non-existence of a private channel if
-                                                       // we don't allow forwards outbound over them.
-                                                       break Some(("Refusing to forward to a private channel based on our config.", 0x4000 | 10, None));
-                                               }
-                                               if chan.get_channel_type().supports_scid_privacy() && *short_channel_id != chan.outbound_scid_alias() {
-                                                       // `option_scid_alias` (referred to in LDK as `scid_privacy`) means
-                                                       // "refuse to forward unless the SCID alias was used", so we pretend
-                                                       // we don't have the channel here.
-                                                       break Some(("Refusing to forward over real channel SCID as our counterparty requested.", 0x4000 | 10, None));
-                                               }
-                                               let chan_update_opt = self.get_channel_update_for_onion(*short_channel_id, chan).ok();
-
-                                               // Note that we could technically not return an error yet here and just hope
-                                               // that the connection is reestablished or monitor updated by the time we get
-                                               // around to doing the actual forward, but better to fail early if we can and
-                                               // hopefully an attacker trying to path-trace payments cannot make this occur
-                                               // on a small/per-node/per-channel scale.
-                                               if !chan.is_live() { // channel_disabled
-                                                       break Some(("Forwarding channel is not in a ready state.", 0x1000 | 20, chan_update_opt));
-                                               }
-                                               if *outgoing_amt_msat < chan.get_counterparty_htlc_minimum_msat() { // amount_below_minimum
-                                                       break Some(("HTLC amount was below the htlc_minimum_msat", 0x1000 | 11, chan_update_opt));
-                                               }
-                                               if let Err((err, code)) = chan.htlc_satisfies_config(&msg, *outgoing_amt_msat, *outgoing_cltv_value) {
-                                                       break Some((err, code, chan_update_opt));
-                                               }
-                                               chan_update_opt
-                                       } else {
-                                               if (msg.cltv_expiry as u64) < (*outgoing_cltv_value) as u64 + MIN_CLTV_EXPIRY_DELTA as u64 {
-                                                       // We really should set `incorrect_cltv_expiry` here but as we're not
-                                                       // forwarding over a real channel we can't generate a channel_update
-                                                       // for it. Instead we just return a generic temporary_node_failure.
-                                                       break Some((
-                                                               "Forwarding node has tampered with the intended HTLC values or origin node has an obsolete cltv_expiry_delta",
-                                                               0x2000 | 2, None,
-                                                       ));
-                                               }
-                                               None
-                                       };
-
-                                       let cur_height = self.best_block.read().unwrap().height() + 1;
-                                       // Theoretically, channel counterparty shouldn't send us a HTLC expiring now,
-                                       // but we want to be robust wrt to counterparty packet sanitization (see
-                                       // HTLC_FAIL_BACK_BUFFER rationale).
-                                       if msg.cltv_expiry <= cur_height + HTLC_FAIL_BACK_BUFFER as u32 { // expiry_too_soon
-                                               break Some(("CLTV expiry is too close", 0x1000 | 14, chan_update_opt));
-                                       }
-                                       if msg.cltv_expiry > cur_height + CLTV_FAR_FAR_AWAY as u32 { // expiry_too_far
-                                               break Some(("CLTV expiry is too far in the future", 21, None));
-                                       }
-                                       // If the HTLC expires ~now, don't bother trying to forward it to our
-                                       // counterparty. They should fail it anyway, but we don't want to bother with
-                                       // the round-trips or risk them deciding they definitely want the HTLC and
-                                       // force-closing to ensure they get it if we're offline.
-                                       // We previously had a much more aggressive check here which tried to ensure
-                                       // our counterparty receives an HTLC which has *our* risk threshold met on it,
-                                       // but there is no need to do that, and since we're a bit conservative with our
-                                       // risk threshold it just results in failing to forward payments.
-                                       if (*outgoing_cltv_value) as u64 <= (cur_height + LATENCY_GRACE_PERIOD_BLOCKS) as u64 {
-                                               break Some(("Outgoing CLTV value is too soon", 0x1000 | 14, chan_update_opt));
-                                       }
-
-                                       break None;
-                               }
-                               {
-                                       let mut res = VecWriter(Vec::with_capacity(chan_update.serialized_length() + 2 + 8 + 2));
-                                       if let Some(chan_update) = chan_update {
-                                               if code == 0x1000 | 11 || code == 0x1000 | 12 {
-                                                       msg.amount_msat.write(&mut res).expect("Writes cannot fail");
-                                               }
-                                               else if code == 0x1000 | 13 {
-                                                       msg.cltv_expiry.write(&mut res).expect("Writes cannot fail");
-                                               }
-                                               else if code == 0x1000 | 20 {
-                                                       // TODO: underspecified, follow https://github.com/lightning/bolts/issues/791
-                                                       0u16.write(&mut res).expect("Writes cannot fail");
-                                               }
-                                               (chan_update.serialized_length() as u16 + 2).write(&mut res).expect("Writes cannot fail");
-                                               msgs::ChannelUpdate::TYPE.write(&mut res).expect("Writes cannot fail");
-                                               chan_update.write(&mut res).expect("Writes cannot fail");
-                                       } else if code & 0x1000 == 0x1000 {
-                                               // If we're trying to return an error that requires a `channel_update` but
-                                               // we're forwarding to a phantom or intercept "channel" (i.e. cannot
-                                               // generate an update), just use the generic "temporary_node_failure"
-                                               // instead.
-                                               code = 0x2000 | 2;
-                                       }
-                                       return_err!(err, code, &res.0[..]);
-                               }
-                       }
                }
-
-               pending_forward_info
        }
 
        /// Gets the current [`channel_update`] for the given channel. This first checks if the channel is
@@ -2438,16 +2913,16 @@ where
        /// [`channel_update`]: msgs::ChannelUpdate
        /// [`internal_closing_signed`]: Self::internal_closing_signed
        fn get_channel_update_for_broadcast(&self, chan: &Channel<<SP::Target as SignerProvider>::Signer>) -> Result<msgs::ChannelUpdate, LightningError> {
-               if !chan.should_announce() {
+               if !chan.context.should_announce() {
                        return Err(LightningError {
                                err: "Cannot broadcast a channel_update for a private channel".to_owned(),
                                action: msgs::ErrorAction::IgnoreError
                        });
                }
-               if chan.get_short_channel_id().is_none() {
+               if chan.context.get_short_channel_id().is_none() {
                        return Err(LightningError{err: "Channel not yet established".to_owned(), action: msgs::ErrorAction::IgnoreError});
                }
-               log_trace!(self.logger, "Attempting to generate broadcast channel update for channel {}", log_bytes!(chan.channel_id()));
+               log_trace!(self.logger, "Attempting to generate broadcast channel update for channel {}", log_bytes!(chan.context.channel_id()));
                self.get_channel_update_for_unicast(chan)
        }
 
@@ -2463,28 +2938,36 @@ where
        /// [`channel_update`]: msgs::ChannelUpdate
        /// [`internal_closing_signed`]: Self::internal_closing_signed
        fn get_channel_update_for_unicast(&self, chan: &Channel<<SP::Target as SignerProvider>::Signer>) -> Result<msgs::ChannelUpdate, LightningError> {
-               log_trace!(self.logger, "Attempting to generate channel update for channel {}", log_bytes!(chan.channel_id()));
-               let short_channel_id = match chan.get_short_channel_id().or(chan.latest_inbound_scid_alias()) {
+               log_trace!(self.logger, "Attempting to generate channel update for channel {}", log_bytes!(chan.context.channel_id()));
+               let short_channel_id = match chan.context.get_short_channel_id().or(chan.context.latest_inbound_scid_alias()) {
                        None => return Err(LightningError{err: "Channel not yet established".to_owned(), action: msgs::ErrorAction::IgnoreError}),
                        Some(id) => id,
                };
 
                self.get_channel_update_for_onion(short_channel_id, chan)
        }
+
        fn get_channel_update_for_onion(&self, short_channel_id: u64, chan: &Channel<<SP::Target as SignerProvider>::Signer>) -> Result<msgs::ChannelUpdate, LightningError> {
-               log_trace!(self.logger, "Generating channel update for channel {}", log_bytes!(chan.channel_id()));
-               let were_node_one = self.our_network_pubkey.serialize()[..] < chan.get_counterparty_node_id().serialize()[..];
+               log_trace!(self.logger, "Generating channel update for channel {}", log_bytes!(chan.context.channel_id()));
+               let were_node_one = self.our_network_pubkey.serialize()[..] < chan.context.get_counterparty_node_id().serialize()[..];
+
+               let enabled = chan.context.is_usable() && match chan.channel_update_status() {
+                       ChannelUpdateStatus::Enabled => true,
+                       ChannelUpdateStatus::DisabledStaged(_) => true,
+                       ChannelUpdateStatus::Disabled => false,
+                       ChannelUpdateStatus::EnabledStaged(_) => false,
+               };
 
                let unsigned = msgs::UnsignedChannelUpdate {
                        chain_hash: self.genesis_hash,
                        short_channel_id,
-                       timestamp: chan.get_update_time_counter(),
-                       flags: (!were_node_one) as u8 | ((!chan.is_live() as u8) << 1),
-                       cltv_expiry_delta: chan.get_cltv_expiry_delta(),
-                       htlc_minimum_msat: chan.get_counterparty_htlc_minimum_msat(),
-                       htlc_maximum_msat: chan.get_announced_htlc_max_msat(),
-                       fee_base_msat: chan.get_outbound_forwarding_fee_base_msat(),
-                       fee_proportional_millionths: chan.get_fee_proportional_millionths(),
+                       timestamp: chan.context.get_update_time_counter(),
+                       flags: (!were_node_one) as u8 | ((!enabled as u8) << 1),
+                       cltv_expiry_delta: chan.context.get_cltv_expiry_delta(),
+                       htlc_minimum_msat: chan.context.get_counterparty_htlc_minimum_msat(),
+                       htlc_maximum_msat: chan.context.get_announced_htlc_max_msat(),
+                       fee_base_msat: chan.context.get_outbound_forwarding_fee_base_msat(),
+                       fee_proportional_millionths: chan.context.get_fee_proportional_millionths(),
                        excess_data: Vec::new(),
                };
                // Panic on failure to signal LDK should be restarted to retry signing the `ChannelUpdate`.
@@ -2500,29 +2983,28 @@ where
        }
 
        #[cfg(test)]
-       pub(crate) fn test_send_payment_along_path(&self, path: &Vec<RouteHop>, payment_hash: &PaymentHash, payment_secret: &Option<PaymentSecret>, total_value: u64, cur_height: u32, payment_id: PaymentId, keysend_preimage: &Option<PaymentPreimage>, session_priv_bytes: [u8; 32]) -> Result<(), APIError> {
+       pub(crate) fn test_send_payment_along_path(&self, path: &Path, payment_hash: &PaymentHash, recipient_onion: RecipientOnionFields, total_value: u64, cur_height: u32, payment_id: PaymentId, keysend_preimage: &Option<PaymentPreimage>, session_priv_bytes: [u8; 32]) -> Result<(), APIError> {
                let _lck = self.total_consistency_lock.read().unwrap();
-               self.send_payment_along_path(path, payment_hash, payment_secret, total_value, cur_height, payment_id, keysend_preimage, session_priv_bytes)
+               self.send_payment_along_path(path, payment_hash, recipient_onion, total_value, cur_height, payment_id, keysend_preimage, session_priv_bytes)
        }
 
-       fn send_payment_along_path(&self, path: &Vec<RouteHop>, payment_hash: &PaymentHash, payment_secret: &Option<PaymentSecret>, total_value: u64, cur_height: u32, payment_id: PaymentId, keysend_preimage: &Option<PaymentPreimage>, session_priv_bytes: [u8; 32]) -> Result<(), APIError> {
+       fn send_payment_along_path(&self, path: &Path, payment_hash: &PaymentHash, recipient_onion: RecipientOnionFields, total_value: u64, cur_height: u32, payment_id: PaymentId, keysend_preimage: &Option<PaymentPreimage>, session_priv_bytes: [u8; 32]) -> Result<(), APIError> {
                // The top-level caller should hold the total_consistency_lock read lock.
                debug_assert!(self.total_consistency_lock.try_write().is_err());
 
-               log_trace!(self.logger, "Attempting to send payment for path with next hop {}", path.first().unwrap().short_channel_id);
+               log_trace!(self.logger, "Attempting to send payment for path with next hop {}", path.hops.first().unwrap().short_channel_id);
                let prng_seed = self.entropy_source.get_secure_random_bytes();
                let session_priv = SecretKey::from_slice(&session_priv_bytes[..]).expect("RNG is busted");
 
                let onion_keys = onion_utils::construct_onion_keys(&self.secp_ctx, &path, &session_priv)
                        .map_err(|_| APIError::InvalidRoute{err: "Pubkey along hop was maliciously selected".to_owned()})?;
-               let (onion_payloads, htlc_msat, htlc_cltv) = onion_utils::build_onion_payloads(path, total_value, payment_secret, cur_height, keysend_preimage)?;
-               if onion_utils::route_size_insane(&onion_payloads) {
-                       return Err(APIError::InvalidRoute{err: "Route size too large considering onion data".to_owned()});
-               }
-               let onion_packet = onion_utils::construct_onion_packet(onion_payloads, onion_keys, prng_seed, payment_hash);
+               let (onion_payloads, htlc_msat, htlc_cltv) = onion_utils::build_onion_payloads(path, total_value, recipient_onion, cur_height, keysend_preimage)?;
+
+               let onion_packet = onion_utils::construct_onion_packet(onion_payloads, onion_keys, prng_seed, payment_hash)
+                       .map_err(|_| APIError::InvalidRoute { err: "Route size too large considering onion data".to_owned()})?;
 
                let err: Result<(), _> = loop {
-                       let (counterparty_node_id, id) = match self.short_to_chan_info.read().unwrap().get(&path.first().unwrap().short_channel_id) {
+                       let (counterparty_node_id, id) = match self.short_to_chan_info.read().unwrap().get(&path.hops.first().unwrap().short_channel_id) {
                                None => return Err(APIError::ChannelUnavailable{err: "No channel available with first hop!".to_owned()}),
                                Some((cp_id, chan_id)) => (cp_id.clone(), chan_id.clone()),
                        };
@@ -2533,17 +3015,16 @@ where
                        let mut peer_state_lock = peer_state_mutex.lock().unwrap();
                        let peer_state = &mut *peer_state_lock;
                        if let hash_map::Entry::Occupied(mut chan) = peer_state.channel_by_id.entry(id) {
-                               if !chan.get().is_live() {
+                               if !chan.get().context.is_live() {
                                        return Err(APIError::ChannelUnavailable{err: "Peer for first hop currently disconnected".to_owned()});
                                }
-                               let funding_txo = chan.get().get_funding_txo().unwrap();
+                               let funding_txo = chan.get().context.get_funding_txo().unwrap();
                                let send_res = chan.get_mut().send_htlc_and_commit(htlc_msat, payment_hash.clone(),
                                        htlc_cltv, HTLCSource::OutboundRoute {
                                                path: path.clone(),
                                                session_priv: session_priv.clone(),
                                                first_hop_htlc_msat: htlc_msat,
                                                payment_id,
-                                               payment_secret: payment_secret.clone(),
                                        }, onion_packet, &self.logger);
                                match break_chan_entry!(self, send_res, chan) {
                                        Some(monitor_update) => {
@@ -2574,7 +3055,7 @@ where
                        return Ok(());
                };
 
-               match handle_error!(self, err, path.first().unwrap().pubkey) {
+               match handle_error!(self, err, path.hops.first().unwrap().pubkey) {
                        Ok(_) => unreachable!(),
                        Err(e) => {
                                Err(APIError::ChannelUnavailable { err: e.err })
@@ -2628,59 +3109,52 @@ where
        /// irrevocably committed to on our end. In such a case, do NOT retry the payment with a
        /// different route unless you intend to pay twice!
        ///
-       /// # A caution on `payment_secret`
-       ///
-       /// `payment_secret` is unrelated to `payment_hash` (or [`PaymentPreimage`]) and exists to
-       /// authenticate the sender to the recipient and prevent payment-probing (deanonymization)
-       /// attacks. For newer nodes, it will be provided to you in the invoice. If you do not have one,
-       /// the [`Route`] must not contain multiple paths as multi-path payments require a
-       /// recipient-provided `payment_secret`.
-       ///
-       /// If a `payment_secret` *is* provided, we assume that the invoice had the payment_secret
-       /// feature bit set (either as required or as available). If multiple paths are present in the
-       /// [`Route`], we assume the invoice had the basic_mpp feature set.
-       ///
        /// [`Event::PaymentSent`]: events::Event::PaymentSent
        /// [`Event::PaymentFailed`]: events::Event::PaymentFailed
        /// [`UpdateHTLCs`]: events::MessageSendEvent::UpdateHTLCs
        /// [`PeerManager::process_events`]: crate::ln::peer_handler::PeerManager::process_events
        /// [`ChannelMonitorUpdateStatus::InProgress`]: crate::chain::ChannelMonitorUpdateStatus::InProgress
-       pub fn send_payment(&self, route: &Route, payment_hash: PaymentHash, payment_secret: &Option<PaymentSecret>, payment_id: PaymentId) -> Result<(), PaymentSendFailure> {
+       pub fn send_payment_with_route(&self, route: &Route, payment_hash: PaymentHash, recipient_onion: RecipientOnionFields, payment_id: PaymentId) -> Result<(), PaymentSendFailure> {
                let best_block_height = self.best_block.read().unwrap().height();
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
                self.pending_outbound_payments
-                       .send_payment_with_route(route, payment_hash, payment_secret, payment_id, &self.entropy_source, &self.node_signer, best_block_height,
-                               |path, payment_hash, payment_secret, total_value, cur_height, payment_id, keysend_preimage, session_priv|
-                               self.send_payment_along_path(path, payment_hash, payment_secret, total_value, cur_height, payment_id, keysend_preimage, session_priv))
+                       .send_payment_with_route(route, payment_hash, recipient_onion, payment_id, &self.entropy_source, &self.node_signer, best_block_height,
+                               |path, payment_hash, recipient_onion, total_value, cur_height, payment_id, keysend_preimage, session_priv|
+                               self.send_payment_along_path(path, payment_hash, recipient_onion, total_value, cur_height, payment_id, keysend_preimage, session_priv))
        }
 
-       /// Similar to [`ChannelManager::send_payment`], but will automatically find a route based on
+       /// Similar to [`ChannelManager::send_payment_with_route`], but will automatically find a route based on
        /// `route_params` and retry failed payment paths based on `retry_strategy`.
-       pub fn send_payment_with_retry(&self, payment_hash: PaymentHash, payment_secret: &Option<PaymentSecret>, payment_id: PaymentId, route_params: RouteParameters, retry_strategy: Retry) -> Result<(), RetryableSendFailure> {
+       pub fn send_payment(&self, payment_hash: PaymentHash, recipient_onion: RecipientOnionFields, payment_id: PaymentId, route_params: RouteParameters, retry_strategy: Retry) -> Result<(), RetryableSendFailure> {
                let best_block_height = self.best_block.read().unwrap().height();
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
                self.pending_outbound_payments
-                       .send_payment(payment_hash, payment_secret, payment_id, retry_strategy, route_params,
+                       .send_payment(payment_hash, recipient_onion, payment_id, retry_strategy, route_params,
                                &self.router, self.list_usable_channels(), || self.compute_inflight_htlcs(),
                                &self.entropy_source, &self.node_signer, best_block_height, &self.logger,
                                &self.pending_events,
-                               |path, payment_hash, payment_secret, total_value, cur_height, payment_id, keysend_preimage, session_priv|
-                               self.send_payment_along_path(path, payment_hash, payment_secret, total_value, cur_height, payment_id, keysend_preimage, session_priv))
+                               |path, payment_hash, recipient_onion, total_value, cur_height, payment_id, keysend_preimage, session_priv|
+                               self.send_payment_along_path(path, payment_hash, recipient_onion, total_value, cur_height, payment_id, keysend_preimage, session_priv))
        }
 
        #[cfg(test)]
-       pub(super) fn test_send_payment_internal(&self, route: &Route, payment_hash: PaymentHash, payment_secret: &Option<PaymentSecret>, keysend_preimage: Option<PaymentPreimage>, payment_id: PaymentId, recv_value_msat: Option<u64>, onion_session_privs: Vec<[u8; 32]>) -> Result<(), PaymentSendFailure> {
+       pub(super) fn test_send_payment_internal(&self, route: &Route, payment_hash: PaymentHash, recipient_onion: RecipientOnionFields, keysend_preimage: Option<PaymentPreimage>, payment_id: PaymentId, recv_value_msat: Option<u64>, onion_session_privs: Vec<[u8; 32]>) -> Result<(), PaymentSendFailure> {
                let best_block_height = self.best_block.read().unwrap().height();
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
-               self.pending_outbound_payments.test_send_payment_internal(route, payment_hash, payment_secret, keysend_preimage, payment_id, recv_value_msat, onion_session_privs, &self.node_signer, best_block_height,
-                       |path, payment_hash, payment_secret, total_value, cur_height, payment_id, keysend_preimage, session_priv|
-                       self.send_payment_along_path(path, payment_hash, payment_secret, total_value, cur_height, payment_id, keysend_preimage, session_priv))
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
+               self.pending_outbound_payments.test_send_payment_internal(route, payment_hash, recipient_onion, keysend_preimage, payment_id, recv_value_msat, onion_session_privs, &self.node_signer, best_block_height,
+                       |path, payment_hash, recipient_onion, total_value, cur_height, payment_id, keysend_preimage, session_priv|
+                       self.send_payment_along_path(path, payment_hash, recipient_onion, total_value, cur_height, payment_id, keysend_preimage, session_priv))
        }
 
        #[cfg(test)]
-       pub(crate) fn test_add_new_pending_payment(&self, payment_hash: PaymentHash, payment_secret: Option<PaymentSecret>, payment_id: PaymentId, route: &Route) -> Result<Vec<[u8; 32]>, PaymentSendFailure> {
+       pub(crate) fn test_add_new_pending_payment(&self, payment_hash: PaymentHash, recipient_onion: RecipientOnionFields, payment_id: PaymentId, route: &Route) -> Result<Vec<[u8; 32]>, PaymentSendFailure> {
                let best_block_height = self.best_block.read().unwrap().height();
-               self.pending_outbound_payments.test_add_new_pending_payment(payment_hash, payment_secret, payment_id, route, None, &self.entropy_source, best_block_height)
+               self.pending_outbound_payments.test_add_new_pending_payment(payment_hash, recipient_onion, payment_id, route, None, &self.entropy_source, best_block_height)
+       }
+
+       #[cfg(test)]
+       pub(crate) fn test_set_payment_metadata(&self, payment_id: PaymentId, new_payment_metadata: Option<Vec<u8>>) {
+               self.pending_outbound_payments.test_set_payment_metadata(payment_id, new_payment_metadata);
        }
 
 
@@ -2701,8 +3175,8 @@ where
        /// [`Event::PaymentFailed`]: events::Event::PaymentFailed
        /// [`Event::PaymentSent`]: events::Event::PaymentSent
        pub fn abandon_payment(&self, payment_id: PaymentId) {
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
-               self.pending_outbound_payments.abandon_payment(payment_id, &self.pending_events);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
+               self.pending_outbound_payments.abandon_payment(payment_id, PaymentFailureReason::UserAbandoned, &self.pending_events);
        }
 
        /// Send a spontaneous payment, which is a payment that does not require the recipient to have
@@ -2717,17 +3191,15 @@ where
        /// Similar to regular payments, you MUST NOT reuse a `payment_preimage` value. See
        /// [`send_payment`] for more information about the risks of duplicate preimage usage.
        ///
-       /// Note that `route` must have exactly one path.
-       ///
        /// [`send_payment`]: Self::send_payment
-       pub fn send_spontaneous_payment(&self, route: &Route, payment_preimage: Option<PaymentPreimage>, payment_id: PaymentId) -> Result<PaymentHash, PaymentSendFailure> {
+       pub fn send_spontaneous_payment(&self, route: &Route, payment_preimage: Option<PaymentPreimage>, recipient_onion: RecipientOnionFields, payment_id: PaymentId) -> Result<PaymentHash, PaymentSendFailure> {
                let best_block_height = self.best_block.read().unwrap().height();
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
                self.pending_outbound_payments.send_spontaneous_payment_with_route(
-                       route, payment_preimage, payment_id, &self.entropy_source, &self.node_signer,
-                       best_block_height,
-                       |path, payment_hash, payment_secret, total_value, cur_height, payment_id, keysend_preimage, session_priv|
-                       self.send_payment_along_path(path, payment_hash, payment_secret, total_value, cur_height, payment_id, keysend_preimage, session_priv))
+                       route, payment_preimage, recipient_onion, payment_id, &self.entropy_source,
+                       &self.node_signer, best_block_height,
+                       |path, payment_hash, recipient_onion, total_value, cur_height, payment_id, keysend_preimage, session_priv|
+                       self.send_payment_along_path(path, payment_hash, recipient_onion, total_value, cur_height, payment_id, keysend_preimage, session_priv))
        }
 
        /// Similar to [`ChannelManager::send_spontaneous_payment`], but will automatically find a route
@@ -2737,26 +3209,26 @@ where
        /// payments.
        ///
        /// [`PaymentParameters::for_keysend`]: crate::routing::router::PaymentParameters::for_keysend
-       pub fn send_spontaneous_payment_with_retry(&self, payment_preimage: Option<PaymentPreimage>, payment_id: PaymentId, route_params: RouteParameters, retry_strategy: Retry) -> Result<PaymentHash, RetryableSendFailure> {
+       pub fn send_spontaneous_payment_with_retry(&self, payment_preimage: Option<PaymentPreimage>, recipient_onion: RecipientOnionFields, payment_id: PaymentId, route_params: RouteParameters, retry_strategy: Retry) -> Result<PaymentHash, RetryableSendFailure> {
                let best_block_height = self.best_block.read().unwrap().height();
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
-               self.pending_outbound_payments.send_spontaneous_payment(payment_preimage, payment_id,
-                       retry_strategy, route_params, &self.router, self.list_usable_channels(),
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
+               self.pending_outbound_payments.send_spontaneous_payment(payment_preimage, recipient_onion,
+                       payment_id, retry_strategy, route_params, &self.router, self.list_usable_channels(),
                        || self.compute_inflight_htlcs(),  &self.entropy_source, &self.node_signer, best_block_height,
                        &self.logger, &self.pending_events,
-                       |path, payment_hash, payment_secret, total_value, cur_height, payment_id, keysend_preimage, session_priv|
-                       self.send_payment_along_path(path, payment_hash, payment_secret, total_value, cur_height, payment_id, keysend_preimage, session_priv))
+                       |path, payment_hash, recipient_onion, total_value, cur_height, payment_id, keysend_preimage, session_priv|
+                       self.send_payment_along_path(path, payment_hash, recipient_onion, total_value, cur_height, payment_id, keysend_preimage, session_priv))
        }
 
        /// Send a payment that is probing the given route for liquidity. We calculate the
        /// [`PaymentHash`] of probes based on a static secret and a random [`PaymentId`], which allows
        /// us to easily discern them from real payments.
-       pub fn send_probe(&self, hops: Vec<RouteHop>) -> Result<(PaymentHash, PaymentId), PaymentSendFailure> {
+       pub fn send_probe(&self, path: Path) -> Result<(PaymentHash, PaymentId), PaymentSendFailure> {
                let best_block_height = self.best_block.read().unwrap().height();
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
-               self.pending_outbound_payments.send_probe(hops, self.probing_cookie_secret, &self.entropy_source, &self.node_signer, best_block_height,
-                       |path, payment_hash, payment_secret, total_value, cur_height, payment_id, keysend_preimage, session_priv|
-                       self.send_payment_along_path(path, payment_hash, payment_secret, total_value, cur_height, payment_id, keysend_preimage, session_priv))
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
+               self.pending_outbound_payments.send_probe(path, self.probing_cookie_secret, &self.entropy_source, &self.node_signer, best_block_height,
+                       |path, payment_hash, recipient_onion, total_value, cur_height, payment_id, keysend_preimage, session_priv|
+                       self.send_payment_along_path(path, payment_hash, recipient_onion, total_value, cur_height, payment_id, keysend_preimage, session_priv))
        }
 
        /// Returns whether a payment with the given [`PaymentHash`] and [`PaymentId`] is, in fact, a
@@ -2768,7 +3240,7 @@ where
 
        /// Handles the generation of a funding transaction, optionally (for tests) with a function
        /// which checks the correctness of the funding transaction given the associated channel.
-       fn funding_transaction_generated_intern<FundingOutput: Fn(&Channel<<SP::Target as SignerProvider>::Signer>, &Transaction) -> Result<OutPoint, APIError>>(
+       fn funding_transaction_generated_intern<FundingOutput: Fn(&OutboundV1Channel<<SP::Target as SignerProvider>::Signer>, &Transaction) -> Result<OutPoint, APIError>>(
                &self, temporary_channel_id: &[u8; 32], counterparty_node_id: &PublicKey, funding_transaction: Transaction, find_funding_output: FundingOutput
        ) -> Result<(), APIError> {
                let per_peer_state = self.per_peer_state.read().unwrap();
@@ -2777,42 +3249,50 @@ where
 
                let mut peer_state_lock = peer_state_mutex.lock().unwrap();
                let peer_state = &mut *peer_state_lock;
-               let (chan, msg) = {
-                       let (res, chan) = {
-                               match peer_state.channel_by_id.remove(temporary_channel_id) {
-                                       Some(mut chan) => {
-                                               let funding_txo = find_funding_output(&chan, &funding_transaction)?;
-
-                                               (chan.get_outbound_funding_created(funding_transaction, funding_txo, &self.logger)
-                                                       .map_err(|e| if let ChannelError::Close(msg) = e {
-                                                               MsgHandleErrInternal::from_finish_shutdown(msg, chan.channel_id(), chan.get_user_id(), chan.force_shutdown(true), None)
-                                                       } else { unreachable!(); })
-                                               , chan)
+               let (chan, msg) = match peer_state.outbound_v1_channel_by_id.remove(temporary_channel_id) {
+                       Some(chan) => {
+                               let funding_txo = find_funding_output(&chan, &funding_transaction)?;
+
+                               let funding_res = chan.get_outbound_funding_created(funding_transaction, funding_txo, &self.logger)
+                                       .map_err(|(mut chan, e)| if let ChannelError::Close(msg) = e {
+                                               let channel_id = chan.context.channel_id();
+                                               let user_id = chan.context.get_user_id();
+                                               let shutdown_res = chan.context.force_shutdown(false);
+                                               (chan, MsgHandleErrInternal::from_finish_shutdown(msg, channel_id, user_id, shutdown_res, None))
+                                       } else { unreachable!(); });
+                               match funding_res {
+                                       Ok((chan, funding_msg)) => (chan, funding_msg),
+                                       Err((chan, err)) => {
+                                               mem::drop(peer_state_lock);
+                                               mem::drop(per_peer_state);
+
+                                               let _: Result<(), _> = handle_error!(self, Err(err), chan.context.get_counterparty_node_id());
+                                               return Err(APIError::ChannelUnavailable {
+                                                       err: "Signer refused to sign the initial commitment transaction".to_owned()
+                                               });
                                        },
-                                       None => { return Err(APIError::ChannelUnavailable { err: format!("Channel with id {} not found for the passed counterparty node_id {}", log_bytes!(*temporary_channel_id), counterparty_node_id) }) },
                                }
-                       };
-                       match handle_error!(self, res, chan.get_counterparty_node_id()) {
-                               Ok(funding_msg) => {
-                                       (chan, funding_msg)
-                               },
-                               Err(_) => { return Err(APIError::ChannelUnavailable {
-                                       err: "Signer refused to sign the initial commitment transaction".to_owned()
-                               }) },
-                       }
+                       },
+                       None => {
+                               return Err(APIError::ChannelUnavailable {
+                                       err: format!(
+                                               "Channel with id {} not found for the passed counterparty node_id {}",
+                                               log_bytes!(*temporary_channel_id), counterparty_node_id),
+                               })
+                       },
                };
 
                peer_state.pending_msg_events.push(events::MessageSendEvent::SendFundingCreated {
-                       node_id: chan.get_counterparty_node_id(),
+                       node_id: chan.context.get_counterparty_node_id(),
                        msg,
                });
-               match peer_state.channel_by_id.entry(chan.channel_id()) {
+               match peer_state.channel_by_id.entry(chan.context.channel_id()) {
                        hash_map::Entry::Occupied(_) => {
                                panic!("Generated duplicate funding txid?");
                        },
                        hash_map::Entry::Vacant(e) => {
                                let mut id_to_peer = self.id_to_peer.lock().unwrap();
-                               if id_to_peer.insert(chan.channel_id(), chan.get_counterparty_node_id()).is_some() {
+                               if id_to_peer.insert(chan.context.channel_id(), chan.context.get_counterparty_node_id()).is_some() {
                                        panic!("id_to_peer map already contained funding txid, which shouldn't be possible");
                                }
                                e.insert(chan);
@@ -2859,7 +3339,7 @@ where
        /// [`Event::FundingGenerationReady`]: crate::events::Event::FundingGenerationReady
        /// [`Event::ChannelClosed`]: crate::events::Event::ChannelClosed
        pub fn funding_transaction_generated(&self, temporary_channel_id: &[u8; 32], counterparty_node_id: &PublicKey, funding_transaction: Transaction) -> Result<(), APIError> {
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
 
                for inp in funding_transaction.input.iter() {
                        if inp.witness.is_empty() {
@@ -2870,30 +3350,32 @@ where
                }
                {
                        let height = self.best_block.read().unwrap().height();
-                       // Transactions are evaluated as final by network mempools at the next block. However, the modules
-                       // constituting our Lightning node might not have perfect sync about their blockchain views. Thus, if
-                       // the wallet module is in advance on the LDK view, allow one more block of headroom.
-                       if !funding_transaction.input.iter().all(|input| input.sequence == Sequence::MAX) && LockTime::from(funding_transaction.lock_time).is_block_height() && funding_transaction.lock_time.0 > height + 2 {
+                       // Transactions are evaluated as final by network mempools if their locktime is strictly
+                       // lower than the next block height. However, the modules constituting our Lightning
+                       // node might not have perfect sync about their blockchain views. Thus, if the wallet
+                       // module is ahead of LDK, only allow one more block of headroom.
+                       if !funding_transaction.input.iter().all(|input| input.sequence == Sequence::MAX) && LockTime::from(funding_transaction.lock_time).is_block_height() && funding_transaction.lock_time.0 > height + 1 {
                                return Err(APIError::APIMisuseError {
                                        err: "Funding transaction absolute timelock is non-final".to_owned()
                                });
                        }
                }
                self.funding_transaction_generated_intern(temporary_channel_id, counterparty_node_id, funding_transaction, |chan, tx| {
+                       if tx.output.len() > u16::max_value() as usize {
+                               return Err(APIError::APIMisuseError {
+                                       err: "Transaction had more than 2^16 outputs, which is not supported".to_owned()
+                               });
+                       }
+
                        let mut output_index = None;
-                       let expected_spk = chan.get_funding_redeemscript().to_v0_p2wsh();
+                       let expected_spk = chan.context.get_funding_redeemscript().to_v0_p2wsh();
                        for (idx, outp) in tx.output.iter().enumerate() {
-                               if outp.script_pubkey == expected_spk && outp.value == chan.get_value_satoshis() {
+                               if outp.script_pubkey == expected_spk && outp.value == chan.context.get_value_satoshis() {
                                        if output_index.is_some() {
                                                return Err(APIError::APIMisuseError {
                                                        err: "Multiple outputs matched the expected script and value".to_owned()
                                                });
                                        }
-                                       if idx > u16::max_value() as usize {
-                                               return Err(APIError::APIMisuseError {
-                                                       err: "Transaction had more than 2^16 outputs, which is not supported".to_owned()
-                                               });
-                                       }
                                        output_index = Some(idx as u16);
                                }
                        }
@@ -2906,7 +3388,7 @@ where
                })
        }
 
-       /// Atomically updates the [`ChannelConfig`] for the given channels.
+       /// Atomically applies partial updates to the [`ChannelConfig`] of the given channels.
        ///
        /// Once the updates are applied, each eligible channel (advertised with a known short channel
        /// ID and a change in [`forwarding_fee_proportional_millionths`], [`forwarding_fee_base_msat`],
@@ -2928,18 +3410,16 @@ where
        /// [`ChannelUpdate`]: msgs::ChannelUpdate
        /// [`ChannelUnavailable`]: APIError::ChannelUnavailable
        /// [`APIMisuseError`]: APIError::APIMisuseError
-       pub fn update_channel_config(
-               &self, counterparty_node_id: &PublicKey, channel_ids: &[[u8; 32]], config: &ChannelConfig,
+       pub fn update_partial_channel_config(
+               &self, counterparty_node_id: &PublicKey, channel_ids: &[[u8; 32]], config_update: &ChannelConfigUpdate,
        ) -> Result<(), APIError> {
-               if config.cltv_expiry_delta < MIN_CLTV_EXPIRY_DELTA {
+               if config_update.cltv_expiry_delta.map(|delta| delta < MIN_CLTV_EXPIRY_DELTA).unwrap_or(false) {
                        return Err(APIError::APIMisuseError {
                                err: format!("The chosen CLTV expiry delta is below the minimum of {}", MIN_CLTV_EXPIRY_DELTA),
                        });
                }
 
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(
-                       &self.total_consistency_lock, &self.persistence_notifier,
-               );
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
                let per_peer_state = self.per_peer_state.read().unwrap();
                let peer_state_mutex = per_peer_state.get(counterparty_node_id)
                        .ok_or_else(|| APIError::ChannelUnavailable { err: format!("Can't find a peer matching the passed counterparty node_id {}", counterparty_node_id) })?;
@@ -2954,14 +3434,16 @@ where
                }
                for channel_id in channel_ids {
                        let channel = peer_state.channel_by_id.get_mut(channel_id).unwrap();
-                       if !channel.update_config(config) {
+                       let mut config = channel.context.config();
+                       config.apply(config_update);
+                       if !channel.context.update_config(&config) {
                                continue;
                        }
                        if let Ok(msg) = self.get_channel_update_for_broadcast(channel) {
                                peer_state.pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate { msg });
                        } else if let Ok(msg) = self.get_channel_update_for_unicast(channel) {
                                peer_state.pending_msg_events.push(events::MessageSendEvent::SendChannelUpdate {
-                                       node_id: channel.get_counterparty_node_id(),
+                                       node_id: channel.context.get_counterparty_node_id(),
                                        msg,
                                });
                        }
@@ -2969,6 +3451,34 @@ where
                Ok(())
        }
 
+       /// Atomically updates the [`ChannelConfig`] for the given channels.
+       ///
+       /// Once the updates are applied, each eligible channel (advertised with a known short channel
+       /// ID and a change in [`forwarding_fee_proportional_millionths`], [`forwarding_fee_base_msat`],
+       /// or [`cltv_expiry_delta`]) has a [`BroadcastChannelUpdate`] event message generated
+       /// containing the new [`ChannelUpdate`] message which should be broadcast to the network.
+       ///
+       /// Returns [`ChannelUnavailable`] when a channel is not found or an incorrect
+       /// `counterparty_node_id` is provided.
+       ///
+       /// Returns [`APIMisuseError`] when a [`cltv_expiry_delta`] update is to be applied with a value
+       /// below [`MIN_CLTV_EXPIRY_DELTA`].
+       ///
+       /// If an error is returned, none of the updates should be considered applied.
+       ///
+       /// [`forwarding_fee_proportional_millionths`]: ChannelConfig::forwarding_fee_proportional_millionths
+       /// [`forwarding_fee_base_msat`]: ChannelConfig::forwarding_fee_base_msat
+       /// [`cltv_expiry_delta`]: ChannelConfig::cltv_expiry_delta
+       /// [`BroadcastChannelUpdate`]: events::MessageSendEvent::BroadcastChannelUpdate
+       /// [`ChannelUpdate`]: msgs::ChannelUpdate
+       /// [`ChannelUnavailable`]: APIError::ChannelUnavailable
+       /// [`APIMisuseError`]: APIError::APIMisuseError
+       pub fn update_channel_config(
+               &self, counterparty_node_id: &PublicKey, channel_ids: &[[u8; 32]], config: &ChannelConfig,
+       ) -> Result<(), APIError> {
+               return self.update_partial_channel_config(counterparty_node_id, channel_ids, &(*config).into());
+       }
+
        /// Attempts to forward an intercepted HTLC over the provided channel id and with the provided
        /// amount to forward. Should only be called in response to an [`HTLCIntercepted`] event.
        ///
@@ -2982,17 +3492,20 @@ where
        /// [`ChannelManager::fail_intercepted_htlc`] MUST be called in response to the event.
        ///
        /// Note that LDK does not enforce fee requirements in `amt_to_forward_msat`, and will not stop
-       /// you from forwarding more than you received.
+       /// you from forwarding more than you received. See
+       /// [`HTLCIntercepted::expected_outbound_amount_msat`] for more on forwarding a different amount
+       /// than expected.
        ///
        /// Errors if the event was not handled in time, in which case the HTLC was automatically failed
        /// backwards.
        ///
        /// [`UserConfig::accept_intercept_htlcs`]: crate::util::config::UserConfig::accept_intercept_htlcs
        /// [`HTLCIntercepted`]: events::Event::HTLCIntercepted
+       /// [`HTLCIntercepted::expected_outbound_amount_msat`]: events::Event::HTLCIntercepted::expected_outbound_amount_msat
        // TODO: when we move to deciding the best outbound channel at forward time, only take
        // `next_node_id` and not `next_hop_channel_id`
        pub fn forward_intercepted_htlc(&self, intercept_id: InterceptId, next_hop_channel_id: &[u8; 32], next_node_id: PublicKey, amt_to_forward_msat: u64) -> Result<(), APIError> {
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
 
                let next_hop_scid = {
                        let peer_state_lock = self.per_peer_state.read().unwrap();
@@ -3002,15 +3515,16 @@ where
                        let peer_state = &mut *peer_state_lock;
                        match peer_state.channel_by_id.get(next_hop_channel_id) {
                                Some(chan) => {
-                                       if !chan.is_usable() {
+                                       if !chan.context.is_usable() {
                                                return Err(APIError::ChannelUnavailable {
                                                        err: format!("Channel with id {} not fully established", log_bytes!(*next_hop_channel_id))
                                                })
                                        }
-                                       chan.get_short_channel_id().unwrap_or(chan.outbound_scid_alias())
+                                       chan.context.get_short_channel_id().unwrap_or(chan.context.outbound_scid_alias())
                                },
                                None => return Err(APIError::ChannelUnavailable {
-                                       err: format!("Channel with id {} not found for the passed counterparty node_id {}", log_bytes!(*next_hop_channel_id), next_node_id)
+                                       err: format!("Funded channel with id {} not found for the passed counterparty node_id {}. Channel may still be opening.",
+                                               log_bytes!(*next_hop_channel_id), next_node_id)
                                })
                        }
                };
@@ -3026,7 +3540,10 @@ where
                        },
                        _ => unreachable!() // Only `PendingHTLCRouting::Forward`s are intercepted
                };
+               let skimmed_fee_msat =
+                       payment.forward_info.outgoing_amt_msat.saturating_sub(amt_to_forward_msat);
                let pending_htlc_info = PendingHTLCInfo {
+                       skimmed_fee_msat: if skimmed_fee_msat == 0 { None } else { Some(skimmed_fee_msat) },
                        outgoing_amt_msat: amt_to_forward_msat, routing, ..payment.forward_info
                };
 
@@ -3048,7 +3565,7 @@ where
        ///
        /// [`HTLCIntercepted`]: events::Event::HTLCIntercepted
        pub fn fail_intercepted_htlc(&self, intercept_id: InterceptId) -> Result<(), APIError> {
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
 
                let payment = self.pending_intercepted_htlcs.lock().unwrap().remove(&intercept_id)
                        .ok_or_else(|| APIError::APIMisuseError {
@@ -3077,9 +3594,9 @@ where
        /// Should only really ever be called in response to a PendingHTLCsForwardable event.
        /// Will likely generate further events.
        pub fn process_pending_htlc_forwards(&self) {
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
 
-               let mut new_events = Vec::new();
+               let mut new_events = VecDeque::new();
                let mut failed_forwards = Vec::new();
                let mut phantom_receives: Vec<(u64, OutPoint, u128, Vec<(PendingHTLCInfo, u64)>)> = Vec::new();
                {
@@ -3096,7 +3613,7 @@ where
                                                                                prev_short_channel_id, prev_htlc_id, prev_funding_outpoint, prev_user_channel_id,
                                                                                forward_info: PendingHTLCInfo {
                                                                                        routing, incoming_shared_secret, payment_hash, outgoing_amt_msat,
-                                                                                       outgoing_cltv_value, incoming_amt_msat: _
+                                                                                       outgoing_cltv_value, ..
                                                                                }
                                                                        }) => {
                                                                                macro_rules! failure_handler {
@@ -3209,7 +3726,7 @@ where
                                                                                prev_short_channel_id, prev_htlc_id, prev_funding_outpoint, prev_user_channel_id: _,
                                                                                forward_info: PendingHTLCInfo {
                                                                                        incoming_shared_secret, payment_hash, outgoing_amt_msat, outgoing_cltv_value,
-                                                                                       routing: PendingHTLCRouting::Forward { onion_packet, .. }, incoming_amt_msat: _,
+                                                                                       routing: PendingHTLCRouting::Forward { onion_packet, .. }, ..
                                                                                },
                                                                        }) => {
                                                                                log_trace!(self.logger, "Adding HTLC from short id {} with payment_hash {} to channel with short id {} after delay", prev_short_channel_id, log_bytes!(payment_hash.0), short_chan_id);
@@ -3233,7 +3750,7 @@ where
                                                                                        let (failure_code, data) = self.get_htlc_temp_fail_err_and_data(0x1000|7, short_chan_id, chan.get());
                                                                                        failed_forwards.push((htlc_source, payment_hash,
                                                                                                HTLCFailReason::reason(failure_code, data),
-                                                                                               HTLCDestination::NextHopChannel { node_id: Some(chan.get().get_counterparty_node_id()), channel_id: forward_chan_id }
+                                                                                               HTLCDestination::NextHopChannel { node_id: Some(chan.get().context.get_counterparty_node_id()), channel_id: forward_chan_id }
                                                                                        ));
                                                                                        continue;
                                                                                }
@@ -3262,26 +3779,36 @@ where
                                                }
                                        }
                                } else {
-                                       for forward_info in pending_forwards.drain(..) {
+                                       'next_forwardable_htlc: for forward_info in pending_forwards.drain(..) {
                                                match forward_info {
                                                        HTLCForwardInfo::AddHTLC(PendingAddHTLCInfo {
                                                                prev_short_channel_id, prev_htlc_id, prev_funding_outpoint, prev_user_channel_id,
                                                                forward_info: PendingHTLCInfo {
-                                                                       routing, incoming_shared_secret, payment_hash, incoming_amt_msat, outgoing_amt_msat, ..
+                                                                       routing, incoming_shared_secret, payment_hash, incoming_amt_msat, outgoing_amt_msat,
+                                                                       skimmed_fee_msat, ..
                                                                }
                                                        }) => {
-                                                               let (cltv_expiry, onion_payload, payment_data, phantom_shared_secret) = match routing {
-                                                                       PendingHTLCRouting::Receive { payment_data, incoming_cltv_expiry, phantom_shared_secret } => {
+                                                               let (cltv_expiry, onion_payload, payment_data, phantom_shared_secret, mut onion_fields) = match routing {
+                                                                       PendingHTLCRouting::Receive { payment_data, payment_metadata, incoming_cltv_expiry, phantom_shared_secret } => {
                                                                                let _legacy_hop_data = Some(payment_data.clone());
-                                                                               (incoming_cltv_expiry, OnionPayload::Invoice { _legacy_hop_data }, Some(payment_data), phantom_shared_secret)
+                                                                               let onion_fields =
+                                                                                       RecipientOnionFields { payment_secret: Some(payment_data.payment_secret), payment_metadata };
+                                                                               (incoming_cltv_expiry, OnionPayload::Invoice { _legacy_hop_data },
+                                                                                       Some(payment_data), phantom_shared_secret, onion_fields)
+                                                                       },
+                                                                       PendingHTLCRouting::ReceiveKeysend { payment_data, payment_preimage, payment_metadata, incoming_cltv_expiry } => {
+                                                                               let onion_fields = RecipientOnionFields {
+                                                                                       payment_secret: payment_data.as_ref().map(|data| data.payment_secret),
+                                                                                       payment_metadata
+                                                                               };
+                                                                               (incoming_cltv_expiry, OnionPayload::Spontaneous(payment_preimage),
+                                                                                       payment_data, None, onion_fields)
                                                                        },
-                                                                       PendingHTLCRouting::ReceiveKeysend { payment_preimage, incoming_cltv_expiry } =>
-                                                                               (incoming_cltv_expiry, OnionPayload::Spontaneous(payment_preimage), None, None),
                                                                        _ => {
                                                                                panic!("short_channel_id == 0 should imply any pending_forward entries are of type Receive");
                                                                        }
                                                                };
-                                                               let mut claimable_htlc = ClaimableHTLC {
+                                                               let claimable_htlc = ClaimableHTLC {
                                                                        prev_hop: HTLCPreviousHopData {
                                                                                short_channel_id: prev_short_channel_id,
                                                                                outpoint: prev_funding_outpoint,
@@ -3299,10 +3826,14 @@ where
                                                                        total_msat: if let Some(data) = &payment_data { data.total_msat } else { outgoing_amt_msat },
                                                                        cltv_expiry,
                                                                        onion_payload,
+                                                                       counterparty_skimmed_fee_msat: skimmed_fee_msat,
                                                                };
 
+                                                               let mut committed_to_claimable = false;
+
                                                                macro_rules! fail_htlc {
                                                                        ($htlc: expr, $payment_hash: expr) => {
+                                                                               debug_assert!(!committed_to_claimable);
                                                                                let mut htlc_msat_height_data = $htlc.value.to_be_bytes().to_vec();
                                                                                htlc_msat_height_data.extend_from_slice(
                                                                                        &self.best_block.read().unwrap().height().to_be_bytes(),
@@ -3317,6 +3848,7 @@ where
                                                                                        HTLCFailReason::reason(0x4000 | 15, htlc_msat_height_data),
                                                                                        HTLCDestination::FailedPayment { payment_hash: $payment_hash },
                                                                                ));
+                                                                               continue 'next_forwardable_htlc;
                                                                        }
                                                                }
                                                                let phantom_shared_secret = claimable_htlc.prev_hop.phantom_shared_secret;
@@ -3327,70 +3859,89 @@ where
                                                                }
 
                                                                macro_rules! check_total_value {
-                                                                       ($payment_data: expr, $payment_preimage: expr) => {{
+                                                                       ($purpose: expr) => {{
                                                                                let mut payment_claimable_generated = false;
-                                                                               let purpose = || {
-                                                                                       events::PaymentPurpose::InvoicePayment {
-                                                                                               payment_preimage: $payment_preimage,
-                                                                                               payment_secret: $payment_data.payment_secret,
-                                                                                       }
+                                                                               let is_keysend = match $purpose {
+                                                                                       events::PaymentPurpose::SpontaneousPayment(_) => true,
+                                                                                       events::PaymentPurpose::InvoicePayment { .. } => false,
                                                                                };
                                                                                let mut claimable_payments = self.claimable_payments.lock().unwrap();
                                                                                if claimable_payments.pending_claiming_payments.contains_key(&payment_hash) {
                                                                                        fail_htlc!(claimable_htlc, payment_hash);
-                                                                                       continue
                                                                                }
-                                                                               let (_, ref mut htlcs) = claimable_payments.claimable_htlcs.entry(payment_hash)
-                                                                                       .or_insert_with(|| (purpose(), Vec::new()));
-                                                                               if htlcs.len() == 1 {
-                                                                                       if let OnionPayload::Spontaneous(_) = htlcs[0].onion_payload {
-                                                                                               log_trace!(self.logger, "Failing new HTLC with payment_hash {} as we already had an existing keysend HTLC with the same payment hash", log_bytes!(payment_hash.0));
+                                                                               let ref mut claimable_payment = claimable_payments.claimable_payments
+                                                                                       .entry(payment_hash)
+                                                                                       // Note that if we insert here we MUST NOT fail_htlc!()
+                                                                                       .or_insert_with(|| {
+                                                                                               committed_to_claimable = true;
+                                                                                               ClaimablePayment {
+                                                                                                       purpose: $purpose.clone(), htlcs: Vec::new(), onion_fields: None,
+                                                                                               }
+                                                                                       });
+                                                                               if $purpose != claimable_payment.purpose {
+                                                                                       let log_keysend = |keysend| if keysend { "keysend" } else { "non-keysend" };
+                                                                                       log_trace!(self.logger, "Failing new {} HTLC with payment_hash {} as we already had an existing {} HTLC with the same payment hash", log_keysend(is_keysend), log_bytes!(payment_hash.0), log_keysend(!is_keysend));
+                                                                                       fail_htlc!(claimable_htlc, payment_hash);
+                                                                               }
+                                                                               if !self.default_configuration.accept_mpp_keysend && is_keysend && !claimable_payment.htlcs.is_empty() {
+                                                                                       log_trace!(self.logger, "Failing new keysend HTLC with payment_hash {} as we already had an existing keysend HTLC with the same payment hash and our config states we don't accept MPP keysend", log_bytes!(payment_hash.0));
+                                                                                       fail_htlc!(claimable_htlc, payment_hash);
+                                                                               }
+                                                                               if let Some(earlier_fields) = &mut claimable_payment.onion_fields {
+                                                                                       if earlier_fields.check_merge(&mut onion_fields).is_err() {
                                                                                                fail_htlc!(claimable_htlc, payment_hash);
-                                                                                               continue
                                                                                        }
+                                                                               } else {
+                                                                                       claimable_payment.onion_fields = Some(onion_fields);
                                                                                }
+                                                                               let ref mut htlcs = &mut claimable_payment.htlcs;
                                                                                let mut total_value = claimable_htlc.sender_intended_value;
+                                                                               let mut earliest_expiry = claimable_htlc.cltv_expiry;
                                                                                for htlc in htlcs.iter() {
                                                                                        total_value += htlc.sender_intended_value;
-                                                                                       match &htlc.onion_payload {
-                                                                                               OnionPayload::Invoice { .. } => {
-                                                                                                       if htlc.total_msat != $payment_data.total_msat {
-                                                                                                               log_trace!(self.logger, "Failing HTLCs with payment_hash {} as the HTLCs had inconsistent total values (eg {} and {})",
-                                                                                                                       log_bytes!(payment_hash.0), $payment_data.total_msat, htlc.total_msat);
-                                                                                                               total_value = msgs::MAX_VALUE_MSAT;
-                                                                                                       }
-                                                                                                       if total_value >= msgs::MAX_VALUE_MSAT { break; }
-                                                                                               },
-                                                                                               _ => unreachable!(),
+                                                                                       earliest_expiry = cmp::min(earliest_expiry, htlc.cltv_expiry);
+                                                                                       if htlc.total_msat != claimable_htlc.total_msat {
+                                                                                               log_trace!(self.logger, "Failing HTLCs with payment_hash {} as the HTLCs had inconsistent total values (eg {} and {})",
+                                                                                                       log_bytes!(payment_hash.0), claimable_htlc.total_msat, htlc.total_msat);
+                                                                                               total_value = msgs::MAX_VALUE_MSAT;
                                                                                        }
+                                                                                       if total_value >= msgs::MAX_VALUE_MSAT { break; }
                                                                                }
                                                                                // The condition determining whether an MPP is complete must
                                                                                // match exactly the condition used in `timer_tick_occurred`
                                                                                if total_value >= msgs::MAX_VALUE_MSAT {
                                                                                        fail_htlc!(claimable_htlc, payment_hash);
-                                                                               } else if total_value - claimable_htlc.sender_intended_value >= $payment_data.total_msat {
+                                                                               } else if total_value - claimable_htlc.sender_intended_value >= claimable_htlc.total_msat {
                                                                                        log_trace!(self.logger, "Failing HTLC with payment_hash {} as payment is already claimable",
                                                                                                log_bytes!(payment_hash.0));
                                                                                        fail_htlc!(claimable_htlc, payment_hash);
-                                                                               } else if total_value >= $payment_data.total_msat {
+                                                                               } else if total_value >= claimable_htlc.total_msat {
+                                                                                       #[allow(unused_assignments)] {
+                                                                                               committed_to_claimable = true;
+                                                                                       }
                                                                                        let prev_channel_id = prev_funding_outpoint.to_channel_id();
                                                                                        htlcs.push(claimable_htlc);
                                                                                        let amount_msat = htlcs.iter().map(|htlc| htlc.value).sum();
                                                                                        htlcs.iter_mut().for_each(|htlc| htlc.total_value_received = Some(amount_msat));
-                                                                                       new_events.push(events::Event::PaymentClaimable {
+                                                                                       new_events.push_back((events::Event::PaymentClaimable {
                                                                                                receiver_node_id: Some(receiver_node_id),
                                                                                                payment_hash,
-                                                                                               purpose: purpose(),
+                                                                                               purpose: $purpose,
                                                                                                amount_msat,
                                                                                                via_channel_id: Some(prev_channel_id),
                                                                                                via_user_channel_id: Some(prev_user_channel_id),
-                                                                                       });
+                                                                                               claim_deadline: Some(earliest_expiry - HTLC_FAIL_BACK_BUFFER),
+                                                                                               onion_fields: claimable_payment.onion_fields.clone(),
+                                                                                       }, None));
                                                                                        payment_claimable_generated = true;
                                                                                } else {
                                                                                        // Nothing to do - we haven't reached the total
                                                                                        // payment value yet, wait until we receive more
                                                                                        // MPP parts.
                                                                                        htlcs.push(claimable_htlc);
+                                                                                       #[allow(unused_assignments)] {
+                                                                                               committed_to_claimable = true;
+                                                                                       }
                                                                                }
                                                                                payment_claimable_generated
                                                                        }}
@@ -3413,7 +3964,6 @@ where
                                                                                                        Err(()) => {
                                                                                                                log_trace!(self.logger, "Failing new HTLC with payment_hash {} as payment verification failed", log_bytes!(payment_hash.0));
                                                                                                                fail_htlc!(claimable_htlc, payment_hash);
-                                                                                                               continue
                                                                                                        }
                                                                                                };
                                                                                                if let Some(min_final_cltv_expiry_delta) = min_final_cltv_expiry_delta {
@@ -3422,47 +3972,25 @@ where
                                                                                                                log_trace!(self.logger, "Failing new HTLC with payment_hash {} as its CLTV expiry was too soon (had {}, earliest expected {})",
                                                                                                                        log_bytes!(payment_hash.0), cltv_expiry, expected_min_expiry_height);
                                                                                                                fail_htlc!(claimable_htlc, payment_hash);
-                                                                                                               continue;
                                                                                                        }
                                                                                                }
-                                                                                               check_total_value!(payment_data, payment_preimage);
+                                                                                               let purpose = events::PaymentPurpose::InvoicePayment {
+                                                                                                       payment_preimage: payment_preimage.clone(),
+                                                                                                       payment_secret: payment_data.payment_secret,
+                                                                                               };
+                                                                                               check_total_value!(purpose);
                                                                                        },
                                                                                        OnionPayload::Spontaneous(preimage) => {
-                                                                                               let mut claimable_payments = self.claimable_payments.lock().unwrap();
-                                                                                               if claimable_payments.pending_claiming_payments.contains_key(&payment_hash) {
-                                                                                                       fail_htlc!(claimable_htlc, payment_hash);
-                                                                                                       continue
-                                                                                               }
-                                                                                               match claimable_payments.claimable_htlcs.entry(payment_hash) {
-                                                                                                       hash_map::Entry::Vacant(e) => {
-                                                                                                               let amount_msat = claimable_htlc.value;
-                                                                                                               claimable_htlc.total_value_received = Some(amount_msat);
-                                                                                                               let purpose = events::PaymentPurpose::SpontaneousPayment(preimage);
-                                                                                                               e.insert((purpose.clone(), vec![claimable_htlc]));
-                                                                                                               let prev_channel_id = prev_funding_outpoint.to_channel_id();
-                                                                                                               new_events.push(events::Event::PaymentClaimable {
-                                                                                                                       receiver_node_id: Some(receiver_node_id),
-                                                                                                                       payment_hash,
-                                                                                                                       amount_msat,
-                                                                                                                       purpose,
-                                                                                                                       via_channel_id: Some(prev_channel_id),
-                                                                                                                       via_user_channel_id: Some(prev_user_channel_id),
-                                                                                                               });
-                                                                                                       },
-                                                                                                       hash_map::Entry::Occupied(_) => {
-                                                                                                               log_trace!(self.logger, "Failing new keysend HTLC with payment_hash {} for a duplicative payment hash", log_bytes!(payment_hash.0));
-                                                                                                               fail_htlc!(claimable_htlc, payment_hash);
-                                                                                                       }
-                                                                                               }
+                                                                                               let purpose = events::PaymentPurpose::SpontaneousPayment(preimage);
+                                                                                               check_total_value!(purpose);
                                                                                        }
                                                                                }
                                                                        },
                                                                        hash_map::Entry::Occupied(inbound_payment) => {
-                                                                               if payment_data.is_none() {
+                                                                               if let OnionPayload::Spontaneous(_) = claimable_htlc.onion_payload {
                                                                                        log_trace!(self.logger, "Failing new keysend HTLC with payment_hash {} because we already have an inbound payment with the same payment hash", log_bytes!(payment_hash.0));
                                                                                        fail_htlc!(claimable_htlc, payment_hash);
-                                                                                       continue
-                                                                               };
+                                                                               }
                                                                                let payment_data = payment_data.unwrap();
                                                                                if inbound_payment.get().payment_secret != payment_data.payment_secret {
                                                                                        log_trace!(self.logger, "Failing new HTLC with payment_hash {} as it didn't match our expected payment secret.", log_bytes!(payment_hash.0));
@@ -3472,7 +4000,11 @@ where
                                                                                                log_bytes!(payment_hash.0), payment_data.total_msat, inbound_payment.get().min_value_msat.unwrap());
                                                                                        fail_htlc!(claimable_htlc, payment_hash);
                                                                                } else {
-                                                                                       let payment_claimable_generated = check_total_value!(payment_data, inbound_payment.get().payment_preimage);
+                                                                                       let purpose = events::PaymentPurpose::InvoicePayment {
+                                                                                               payment_preimage: inbound_payment.get().payment_preimage,
+                                                                                               payment_secret: payment_data.payment_secret,
+                                                                                       };
+                                                                                       let payment_claimable_generated = check_total_value!(purpose);
                                                                                        if payment_claimable_generated {
                                                                                                inbound_payment.remove_entry();
                                                                                        }
@@ -3493,8 +4025,8 @@ where
                self.pending_outbound_payments.check_retry_payments(&self.router, || self.list_usable_channels(),
                        || self.compute_inflight_htlcs(), &self.entropy_source, &self.node_signer, best_block_height,
                        &self.pending_events, &self.logger,
-                       |path, payment_hash, payment_secret, total_value, cur_height, payment_id, keysend_preimage, session_priv|
-                       self.send_payment_along_path(path, payment_hash, payment_secret, total_value, cur_height, payment_id, keysend_preimage, session_priv));
+                       |path, payment_hash, recipient_onion, total_value, cur_height, payment_id, keysend_preimage, session_priv|
+                       self.send_payment_along_path(path, payment_hash, recipient_onion, total_value, cur_height, payment_id, keysend_preimage, session_priv));
 
                for (htlc_source, payment_hash, failure_reason, destination) in failed_forwards.drain(..) {
                        self.fail_htlc_backwards_internal(&htlc_source, &payment_hash, &failure_reason, destination);
@@ -3512,52 +4044,80 @@ where
                events.append(&mut new_events);
        }
 
-       /// Free the background events, generally called from timer_tick_occurred.
-       ///
-       /// Exposed for testing to allow us to process events quickly without generating accidental
-       /// BroadcastChannelUpdate events in timer_tick_occurred.
+       /// Free the background events, generally called from [`PersistenceNotifierGuard`] constructors.
        ///
        /// Expects the caller to have a total_consistency_lock read lock.
-       fn process_background_events(&self) -> bool {
+       fn process_background_events(&self) -> NotifyOption {
+               debug_assert_ne!(self.total_consistency_lock.held_by_thread(), LockHeldState::NotHeldByThread);
+
+               #[cfg(debug_assertions)]
+               self.background_events_processed_since_startup.store(true, Ordering::Release);
+
                let mut background_events = Vec::new();
                mem::swap(&mut *self.pending_background_events.lock().unwrap(), &mut background_events);
                if background_events.is_empty() {
-                       return false;
+                       return NotifyOption::SkipPersist;
                }
 
                for event in background_events.drain(..) {
                        match event {
-                               BackgroundEvent::ClosingMonitorUpdate((funding_txo, update)) => {
+                               BackgroundEvent::ClosingMonitorUpdateRegeneratedOnStartup((funding_txo, update)) => {
                                        // The channel has already been closed, so no use bothering to care about the
                                        // monitor updating completing.
                                        let _ = self.chain_monitor.update_channel(funding_txo, &update);
                                },
+                               BackgroundEvent::MonitorUpdateRegeneratedOnStartup { counterparty_node_id, funding_txo, update } => {
+                                       let update_res = self.chain_monitor.update_channel(funding_txo, &update);
+
+                                       let res = {
+                                               let per_peer_state = self.per_peer_state.read().unwrap();
+                                               if let Some(peer_state_mutex) = per_peer_state.get(&counterparty_node_id) {
+                                                       let mut peer_state_lock = peer_state_mutex.lock().unwrap();
+                                                       let peer_state = &mut *peer_state_lock;
+                                                       match peer_state.channel_by_id.entry(funding_txo.to_channel_id()) {
+                                                               hash_map::Entry::Occupied(mut chan) => {
+                                                                       handle_new_monitor_update!(self, update_res, update.update_id, peer_state_lock, peer_state, per_peer_state, chan)
+                                                               },
+                                                               hash_map::Entry::Vacant(_) => Ok(()),
+                                                       }
+                                               } else { Ok(()) }
+                                       };
+                                       // TODO: If this channel has since closed, we're likely providing a payment
+                                       // preimage update, which we must ensure is durable! We currently don't,
+                                       // however, ensure that.
+                                       if res.is_err() {
+                                               log_error!(self.logger,
+                                                       "Failed to provide ChannelMonitorUpdate to closed channel! This likely lost us a payment preimage!");
+                                       }
+                                       let _ = handle_error!(self, res, counterparty_node_id);
+                               },
                        }
                }
-               true
+               NotifyOption::DoPersist
        }
 
        #[cfg(any(test, feature = "_test_utils"))]
        /// Process background events, for functional testing
        pub fn test_process_background_events(&self) {
-               self.process_background_events();
+               let _lck = self.total_consistency_lock.read().unwrap();
+               let _ = self.process_background_events();
        }
 
        fn update_channel_fee(&self, chan_id: &[u8; 32], chan: &mut Channel<<SP::Target as SignerProvider>::Signer>, new_feerate: u32) -> NotifyOption {
-               if !chan.is_outbound() { return NotifyOption::SkipPersist; }
+               if !chan.context.is_outbound() { return NotifyOption::SkipPersist; }
                // If the feerate has decreased by less than half, don't bother
-               if new_feerate <= chan.get_feerate_sat_per_1000_weight() && new_feerate * 2 > chan.get_feerate_sat_per_1000_weight() {
+               if new_feerate <= chan.context.get_feerate_sat_per_1000_weight() && new_feerate * 2 > chan.context.get_feerate_sat_per_1000_weight() {
                        log_trace!(self.logger, "Channel {} does not qualify for a feerate change from {} to {}.",
-                               log_bytes!(chan_id[..]), chan.get_feerate_sat_per_1000_weight(), new_feerate);
+                               log_bytes!(chan_id[..]), chan.context.get_feerate_sat_per_1000_weight(), new_feerate);
                        return NotifyOption::SkipPersist;
                }
-               if !chan.is_live() {
+               if !chan.context.is_live() {
                        log_trace!(self.logger, "Channel {} does not qualify for a feerate change from {} to {} as it cannot currently be updated (probably the peer is disconnected).",
-                               log_bytes!(chan_id[..]), chan.get_feerate_sat_per_1000_weight(), new_feerate);
+                               log_bytes!(chan_id[..]), chan.context.get_feerate_sat_per_1000_weight(), new_feerate);
                        return NotifyOption::SkipPersist;
                }
                log_trace!(self.logger, "Channel {} qualifies for a feerate change from {} to {}.",
-                       log_bytes!(chan_id[..]), chan.get_feerate_sat_per_1000_weight(), new_feerate);
+                       log_bytes!(chan_id[..]), chan.context.get_feerate_sat_per_1000_weight(), new_feerate);
 
                chan.queue_update_fee(new_feerate, &self.logger);
                NotifyOption::DoPersist
@@ -3570,7 +4130,7 @@ where
        /// it wants to detect). Thus, we have a variant exposed here for its benefit.
        pub fn maybe_update_chan_fees(&self) {
                PersistenceNotifierGuard::optionally_notify(&self.total_consistency_lock, &self.persistence_notifier, || {
-                       let mut should_persist = NotifyOption::SkipPersist;
+                       let mut should_persist = self.process_background_events();
 
                        let new_feerate = self.fee_estimator.bounded_sat_per_1000_weight(ConfirmationTarget::Normal);
 
@@ -3606,8 +4166,7 @@ where
        /// [`ChannelConfig`]: crate::util::config::ChannelConfig
        pub fn timer_tick_occurred(&self) {
                PersistenceNotifierGuard::optionally_notify(&self.total_consistency_lock, &self.persistence_notifier, || {
-                       let mut should_persist = NotifyOption::SkipPersist;
-                       if self.process_background_events() { should_persist = NotifyOption::DoPersist; }
+                       let mut should_persist = self.process_background_events();
 
                        let new_feerate = self.fee_estimator.bounded_sat_per_1000_weight(ConfirmationTarget::Normal);
 
@@ -3632,32 +4191,58 @@ where
                                                }
 
                                                match chan.channel_update_status() {
-                                                       ChannelUpdateStatus::Enabled if !chan.is_live() => chan.set_channel_update_status(ChannelUpdateStatus::DisabledStaged),
-                                                       ChannelUpdateStatus::Disabled if chan.is_live() => chan.set_channel_update_status(ChannelUpdateStatus::EnabledStaged),
-                                                       ChannelUpdateStatus::DisabledStaged if chan.is_live() => chan.set_channel_update_status(ChannelUpdateStatus::Enabled),
-                                                       ChannelUpdateStatus::EnabledStaged if !chan.is_live() => chan.set_channel_update_status(ChannelUpdateStatus::Disabled),
-                                                       ChannelUpdateStatus::DisabledStaged if !chan.is_live() => {
-                                                               if let Ok(update) = self.get_channel_update_for_broadcast(&chan) {
-                                                                       pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
-                                                                               msg: update
-                                                                       });
+                                                       ChannelUpdateStatus::Enabled if !chan.context.is_live() => chan.set_channel_update_status(ChannelUpdateStatus::DisabledStaged(0)),
+                                                       ChannelUpdateStatus::Disabled if chan.context.is_live() => chan.set_channel_update_status(ChannelUpdateStatus::EnabledStaged(0)),
+                                                       ChannelUpdateStatus::DisabledStaged(_) if chan.context.is_live()
+                                                               => chan.set_channel_update_status(ChannelUpdateStatus::Enabled),
+                                                       ChannelUpdateStatus::EnabledStaged(_) if !chan.context.is_live()
+                                                               => chan.set_channel_update_status(ChannelUpdateStatus::Disabled),
+                                                       ChannelUpdateStatus::DisabledStaged(mut n) if !chan.context.is_live() => {
+                                                               n += 1;
+                                                               if n >= DISABLE_GOSSIP_TICKS {
+                                                                       chan.set_channel_update_status(ChannelUpdateStatus::Disabled);
+                                                                       if let Ok(update) = self.get_channel_update_for_broadcast(&chan) {
+                                                                               pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
+                                                                                       msg: update
+                                                                               });
+                                                                       }
+                                                                       should_persist = NotifyOption::DoPersist;
+                                                               } else {
+                                                                       chan.set_channel_update_status(ChannelUpdateStatus::DisabledStaged(n));
                                                                }
-                                                               should_persist = NotifyOption::DoPersist;
-                                                               chan.set_channel_update_status(ChannelUpdateStatus::Disabled);
                                                        },
-                                                       ChannelUpdateStatus::EnabledStaged if chan.is_live() => {
-                                                               if let Ok(update) = self.get_channel_update_for_broadcast(&chan) {
-                                                                       pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
-                                                                               msg: update
-                                                                       });
+                                                       ChannelUpdateStatus::EnabledStaged(mut n) if chan.context.is_live() => {
+                                                               n += 1;
+                                                               if n >= ENABLE_GOSSIP_TICKS {
+                                                                       chan.set_channel_update_status(ChannelUpdateStatus::Enabled);
+                                                                       if let Ok(update) = self.get_channel_update_for_broadcast(&chan) {
+                                                                               pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
+                                                                                       msg: update
+                                                                               });
+                                                                       }
+                                                                       should_persist = NotifyOption::DoPersist;
+                                                               } else {
+                                                                       chan.set_channel_update_status(ChannelUpdateStatus::EnabledStaged(n));
                                                                }
-                                                               should_persist = NotifyOption::DoPersist;
-                                                               chan.set_channel_update_status(ChannelUpdateStatus::Enabled);
                                                        },
                                                        _ => {},
                                                }
 
-                                               chan.maybe_expire_prev_config();
+                                               chan.context.maybe_expire_prev_config();
+
+                                               if chan.should_disconnect_peer_awaiting_response() {
+                                                       log_debug!(self.logger, "Disconnecting peer {} due to not making any progress on channel {}",
+                                                                       counterparty_node_id, log_bytes!(*chan_id));
+                                                       pending_msg_events.push(MessageSendEvent::HandleError {
+                                                               node_id: counterparty_node_id,
+                                                               action: msgs::ErrorAction::DisconnectPeerWithWarning {
+                                                                       msg: msgs::WarningMessage {
+                                                                               channel_id: *chan_id,
+                                                                               data: "Disconnecting due to timeout awaiting response".to_owned(),
+                                                                       },
+                                                               },
+                                                       });
+                                               }
 
                                                true
                                        });
@@ -3694,24 +4279,27 @@ where
                                }
                        }
 
-                       self.claimable_payments.lock().unwrap().claimable_htlcs.retain(|payment_hash, (_, htlcs)| {
-                               if htlcs.is_empty() {
+                       self.claimable_payments.lock().unwrap().claimable_payments.retain(|payment_hash, payment| {
+                               if payment.htlcs.is_empty() {
                                        // This should be unreachable
                                        debug_assert!(false);
                                        return false;
                                }
-                               if let OnionPayload::Invoice { .. } = htlcs[0].onion_payload {
+                               if let OnionPayload::Invoice { .. } = payment.htlcs[0].onion_payload {
                                        // Check if we've received all the parts we need for an MPP (the value of the parts adds to total_msat).
                                        // In this case we're not going to handle any timeouts of the parts here.
                                        // This condition determining whether the MPP is complete here must match
                                        // exactly the condition used in `process_pending_htlc_forwards`.
-                                       if htlcs[0].total_msat <= htlcs.iter().fold(0, |total, htlc| total + htlc.sender_intended_value) {
+                                       if payment.htlcs[0].total_msat <= payment.htlcs.iter()
+                                               .fold(0, |total, htlc| total + htlc.sender_intended_value)
+                                       {
                                                return true;
-                                       } else if htlcs.into_iter().any(|htlc| {
+                                       } else if payment.htlcs.iter_mut().any(|htlc| {
                                                htlc.timer_ticks += 1;
                                                return htlc.timer_ticks >= MPP_TIMEOUT_TICKS
                                        }) {
-                                               timed_out_mpp_htlcs.extend(htlcs.drain(..).map(|htlc: ClaimableHTLC| (htlc.prev_hop, *payment_hash)));
+                                               timed_out_mpp_htlcs.extend(payment.htlcs.drain(..)
+                                                       .map(|htlc: ClaimableHTLC| (htlc.prev_hop, *payment_hash)));
                                                return false;
                                        }
                                }
@@ -3764,11 +4352,11 @@ where
        ///
        /// See [`FailureCode`] for valid failure codes.
        pub fn fail_htlc_backwards_with_reason(&self, payment_hash: &PaymentHash, failure_code: FailureCode) {
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
 
-               let removed_source = self.claimable_payments.lock().unwrap().claimable_htlcs.remove(payment_hash);
-               if let Some((_, mut sources)) = removed_source {
-                       for htlc in sources.drain(..) {
+               let removed_source = self.claimable_payments.lock().unwrap().claimable_payments.remove(payment_hash);
+               if let Some(payment) = removed_source {
+                       for htlc in payment.htlcs {
                                let reason = self.get_htlc_fail_reason_from_failure_code(failure_code, &htlc);
                                let source = HTLCSource::PreviousHopData(htlc.prev_hop);
                                let receiver = HTLCDestination::FailedPayment { payment_hash: *payment_hash };
@@ -3800,10 +4388,10 @@ where
                // guess somewhat. If its a public channel, we figure best to just use the real SCID (as
                // we're not leaking that we have a channel with the counterparty), otherwise we try to use
                // an inbound SCID alias before the real SCID.
-               let scid_pref = if chan.should_announce() {
-                       chan.get_short_channel_id().or(chan.latest_inbound_scid_alias())
+               let scid_pref = if chan.context.should_announce() {
+                       chan.context.get_short_channel_id().or(chan.context.latest_inbound_scid_alias())
                } else {
-                       chan.latest_inbound_scid_alias().or(chan.get_short_channel_id())
+                       chan.context.latest_inbound_scid_alias().or(chan.context.get_short_channel_id())
                };
                if let Some(scid) = scid_pref {
                        self.get_htlc_temp_fail_err_and_data(desired_err_code, scid, chan)
@@ -3911,10 +4499,10 @@ where
                                mem::drop(forward_htlcs);
                                if push_forward_ev { self.push_pending_forwards_ev(); }
                                let mut pending_events = self.pending_events.lock().unwrap();
-                               pending_events.push(events::Event::HTLCHandlingFailed {
+                               pending_events.push_back((events::Event::HTLCHandlingFailed {
                                        prev_channel_id: outpoint.to_channel_id(),
                                        failed_next_destination: destination,
-                               });
+                               }, None));
                        },
                }
        }
@@ -3922,9 +4510,10 @@ where
        /// Provides a payment preimage in response to [`Event::PaymentClaimable`], generating any
        /// [`MessageSendEvent`]s needed to claim the payment.
        ///
-       /// Note that calling this method does *not* guarantee that the payment has been claimed. You
-       /// *must* wait for an [`Event::PaymentClaimed`] event which upon a successful claim will be
-       /// provided to your [`EventHandler`] when [`process_pending_events`] is next called.
+       /// This method is guaranteed to ensure the payment has been claimed but only if the current
+       /// height is strictly below [`Event::PaymentClaimable::claim_deadline`]. To avoid race
+       /// conditions, you should wait for an [`Event::PaymentClaimed`] before considering the payment
+       /// successful. It will generally be available in the next [`process_pending_events`] call.
        ///
        /// Note that if you did not set an `amount_msat` when calling [`create_inbound_payment`] or
        /// [`create_inbound_payment_for_hash`] you must check that the amount in the `PaymentClaimable`
@@ -3932,6 +4521,7 @@ where
        /// the sender "proof-of-payment" when they did not fulfill the full expected payment.
        ///
        /// [`Event::PaymentClaimable`]: crate::events::Event::PaymentClaimable
+       /// [`Event::PaymentClaimable::claim_deadline`]: crate::events::Event::PaymentClaimable::claim_deadline
        /// [`Event::PaymentClaimed`]: crate::events::Event::PaymentClaimed
        /// [`process_pending_events`]: EventsProvider::process_pending_events
        /// [`create_inbound_payment`]: Self::create_inbound_payment
@@ -3939,13 +4529,13 @@ where
        pub fn claim_funds(&self, payment_preimage: PaymentPreimage) {
                let payment_hash = PaymentHash(Sha256::hash(&payment_preimage.0).into_inner());
 
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
 
                let mut sources = {
                        let mut claimable_payments = self.claimable_payments.lock().unwrap();
-                       if let Some((payment_purpose, sources)) = claimable_payments.claimable_htlcs.remove(&payment_hash) {
+                       if let Some(payment) = claimable_payments.claimable_payments.remove(&payment_hash) {
                                let mut receiver_node_id = self.our_network_pubkey;
-                               for htlc in sources.iter() {
+                               for htlc in payment.htlcs.iter() {
                                        if htlc.prev_hop.phantom_shared_secret.is_some() {
                                                let phantom_pubkey = self.node_signer.get_node_id(Recipient::PhantomNode)
                                                        .expect("Failed to get node_id for phantom node recipient");
@@ -3955,34 +4545,23 @@ where
                                }
 
                                let dup_purpose = claimable_payments.pending_claiming_payments.insert(payment_hash,
-                                       ClaimingPayment { amount_msat: sources.iter().map(|source| source.value).sum(),
-                                       payment_purpose, receiver_node_id,
+                                       ClaimingPayment { amount_msat: payment.htlcs.iter().map(|source| source.value).sum(),
+                                       payment_purpose: payment.purpose, receiver_node_id,
                                });
                                if dup_purpose.is_some() {
                                        debug_assert!(false, "Shouldn't get a duplicate pending claim event ever");
                                        log_error!(self.logger, "Got a duplicate pending claimable event on payment hash {}! Please report this bug",
                                                log_bytes!(payment_hash.0));
                                }
-                               sources
+                               payment.htlcs
                        } else { return; }
                };
                debug_assert!(!sources.is_empty());
 
-               // If we are claiming an MPP payment, we check that all channels which contain a claimable
-               // HTLC still exist. While this isn't guaranteed to remain true if a channel closes while
-               // we're claiming (or even after we claim, before the commitment update dance completes),
-               // it should be a relatively rare race, and we'd rather not claim HTLCs that require us to
-               // go on-chain (and lose the on-chain fee to do so) than just reject the payment.
-               //
-               // Note that we'll still always get our funds - as long as the generated
-               // `ChannelMonitorUpdate` makes it out to the relevant monitor we can claim on-chain.
-               //
-               // If we find an HTLC which we would need to claim but for which we do not have a
-               // channel, we will fail all parts of the MPP payment. While we could wait and see if
-               // the sender retries the already-failed path(s), it should be a pretty rare case where
-               // we got all the HTLCs and then a channel closed while we were waiting for the user to
-               // provide the preimage, so worrying too much about the optimal handling isn't worth
-               // it.
+               // Just in case one HTLC has been failed between when we generated the `PaymentClaimable`
+               // and when we got here we need to check that the amount we're about to claim matches the
+               // amount we told the user in the last `PaymentClaimable`. We also do a sanity-check that
+               // the MPP parts all have the same `total_msat`.
                let mut claimable_amt_msat = 0;
                let mut prev_total_msat = None;
                let mut expected_amt_msat = None;
@@ -3990,28 +4569,6 @@ where
                let mut errs = Vec::new();
                let per_peer_state = self.per_peer_state.read().unwrap();
                for htlc in sources.iter() {
-                       let (counterparty_node_id, chan_id) = match self.short_to_chan_info.read().unwrap().get(&htlc.prev_hop.short_channel_id) {
-                               Some((cp_id, chan_id)) => (cp_id.clone(), chan_id.clone()),
-                               None => {
-                                       valid_mpp = false;
-                                       break;
-                               }
-                       };
-
-                       let peer_state_mutex_opt = per_peer_state.get(&counterparty_node_id);
-                       if peer_state_mutex_opt.is_none() {
-                               valid_mpp = false;
-                               break;
-                       }
-
-                       let mut peer_state_lock = peer_state_mutex_opt.unwrap().lock().unwrap();
-                       let peer_state = &mut *peer_state_lock;
-
-                       if peer_state.channel_by_id.get(&chan_id).is_none() {
-                               valid_mpp = false;
-                               break;
-                       }
-
                        if prev_total_msat.is_some() && prev_total_msat != Some(htlc.total_msat) {
                                log_error!(self.logger, "Somehow ended up with an MPP payment with different expected total amounts - this should not be reachable!");
                                debug_assert!(false);
@@ -4027,18 +4584,6 @@ where
                                break;
                        }
                        expected_amt_msat = htlc.total_value_received;
-
-                       if let OnionPayload::Spontaneous(_) = &htlc.onion_payload {
-                               // We don't currently support MPP for spontaneous payments, so just check
-                               // that there's one payment here and move on.
-                               if sources.len() != 1 {
-                                       log_error!(self.logger, "Somehow ended up with an MPP spontaneous payment - this should not be reachable!");
-                                       debug_assert!(false);
-                                       valid_mpp = false;
-                                       break;
-                               }
-                       }
-
                        claimable_amt_msat += htlc.value;
                }
                mem::drop(per_peer_state);
@@ -4091,45 +4636,46 @@ where
        -> Result<(), (PublicKey, MsgHandleErrInternal)> {
                //TODO: Delay the claimed_funds relaying just like we do outbound relay!
 
-               let per_peer_state = self.per_peer_state.read().unwrap();
-               let chan_id = prev_hop.outpoint.to_channel_id();
-               let counterparty_node_id_opt = match self.short_to_chan_info.read().unwrap().get(&prev_hop.short_channel_id) {
-                       Some((cp_id, _dup_chan_id)) => Some(cp_id.clone()),
-                       None => None
-               };
+               {
+                       let per_peer_state = self.per_peer_state.read().unwrap();
+                       let chan_id = prev_hop.outpoint.to_channel_id();
+                       let counterparty_node_id_opt = match self.short_to_chan_info.read().unwrap().get(&prev_hop.short_channel_id) {
+                               Some((cp_id, _dup_chan_id)) => Some(cp_id.clone()),
+                               None => None
+                       };
 
-               let peer_state_opt = counterparty_node_id_opt.as_ref().map(
-                       |counterparty_node_id| per_peer_state.get(counterparty_node_id).map(
-                               |peer_mutex| peer_mutex.lock().unwrap()
-                       )
-               ).unwrap_or(None);
+                       let peer_state_opt = counterparty_node_id_opt.as_ref().map(
+                               |counterparty_node_id| per_peer_state.get(counterparty_node_id)
+                                       .map(|peer_mutex| peer_mutex.lock().unwrap())
+                       ).unwrap_or(None);
 
-               if peer_state_opt.is_some() {
-                       let mut peer_state_lock = peer_state_opt.unwrap();
-                       let peer_state = &mut *peer_state_lock;
-                       if let hash_map::Entry::Occupied(mut chan) = peer_state.channel_by_id.entry(chan_id) {
-                               let counterparty_node_id = chan.get().get_counterparty_node_id();
-                               let fulfill_res = chan.get_mut().get_update_fulfill_htlc_and_commit(prev_hop.htlc_id, payment_preimage, &self.logger);
-
-                               if let UpdateFulfillCommitFetch::NewClaim { htlc_value_msat, monitor_update } = fulfill_res {
-                                       if let Some(action) = completion_action(Some(htlc_value_msat)) {
-                                               log_trace!(self.logger, "Tracking monitor update completion action for channel {}: {:?}",
-                                                       log_bytes!(chan_id), action);
-                                               peer_state.monitor_update_blocked_actions.entry(chan_id).or_insert(Vec::new()).push(action);
-                                       }
-                                       let update_id = monitor_update.update_id;
-                                       let update_res = self.chain_monitor.update_channel(prev_hop.outpoint, monitor_update);
-                                       let res = handle_new_monitor_update!(self, update_res, update_id, peer_state_lock,
-                                               peer_state, per_peer_state, chan);
-                                       if let Err(e) = res {
-                                               // TODO: This is a *critical* error - we probably updated the outbound edge
-                                               // of the HTLC's monitor with a preimage. We should retry this monitor
-                                               // update over and over again until morale improves.
-                                               log_error!(self.logger, "Failed to update channel monitor with preimage {:?}", payment_preimage);
-                                               return Err((counterparty_node_id, e));
+                       if peer_state_opt.is_some() {
+                               let mut peer_state_lock = peer_state_opt.unwrap();
+                               let peer_state = &mut *peer_state_lock;
+                               if let hash_map::Entry::Occupied(mut chan) = peer_state.channel_by_id.entry(chan_id) {
+                                       let counterparty_node_id = chan.get().context.get_counterparty_node_id();
+                                       let fulfill_res = chan.get_mut().get_update_fulfill_htlc_and_commit(prev_hop.htlc_id, payment_preimage, &self.logger);
+
+                                       if let UpdateFulfillCommitFetch::NewClaim { htlc_value_msat, monitor_update } = fulfill_res {
+                                               if let Some(action) = completion_action(Some(htlc_value_msat)) {
+                                                       log_trace!(self.logger, "Tracking monitor update completion action for channel {}: {:?}",
+                                                               log_bytes!(chan_id), action);
+                                                       peer_state.monitor_update_blocked_actions.entry(chan_id).or_insert(Vec::new()).push(action);
+                                               }
+                                               let update_id = monitor_update.update_id;
+                                               let update_res = self.chain_monitor.update_channel(prev_hop.outpoint, monitor_update);
+                                               let res = handle_new_monitor_update!(self, update_res, update_id, peer_state_lock,
+                                                       peer_state, per_peer_state, chan);
+                                               if let Err(e) = res {
+                                                       // TODO: This is a *critical* error - we probably updated the outbound edge
+                                                       // of the HTLC's monitor with a preimage. We should retry this monitor
+                                                       // update over and over again until morale improves.
+                                                       log_error!(self.logger, "Failed to update channel monitor with preimage {:?}", payment_preimage);
+                                                       return Err((counterparty_node_id, e));
+                                               }
                                        }
+                                       return Ok(());
                                }
-                               return Ok(());
                        }
                }
                let preimage_update = ChannelMonitorUpdate {
@@ -4176,15 +4722,16 @@ where
                                                                Some(claimed_htlc_value - forwarded_htlc_value)
                                                        } else { None };
 
-                                                       let prev_channel_id = Some(prev_outpoint.to_channel_id());
-                                                       let next_channel_id = Some(next_channel_id);
-
-                                                       Some(MonitorUpdateCompletionAction::EmitEvent { event: events::Event::PaymentForwarded {
-                                                               fee_earned_msat,
-                                                               claim_from_onchain_tx: from_onchain,
-                                                               prev_channel_id,
-                                                               next_channel_id,
-                                                       }})
+                                                       Some(MonitorUpdateCompletionAction::EmitEventAndFreeOtherChannel {
+                                                               event: events::Event::PaymentForwarded {
+                                                                       fee_earned_msat,
+                                                                       claim_from_onchain_tx: from_onchain,
+                                                                       prev_channel_id: Some(prev_outpoint.to_channel_id()),
+                                                                       next_channel_id: Some(next_channel_id),
+                                                                       outbound_amount_forwarded_msat: forwarded_htlc_value_msat,
+                                                               },
+                                                               downstream_counterparty_and_funding_outpoint: None,
+                                                       })
                                                } else { None }
                                        });
                                if let Err((pk, err)) = res {
@@ -4206,13 +4753,18 @@ where
                                MonitorUpdateCompletionAction::PaymentClaimed { payment_hash } => {
                                        let payment = self.claimable_payments.lock().unwrap().pending_claiming_payments.remove(&payment_hash);
                                        if let Some(ClaimingPayment { amount_msat, payment_purpose: purpose, receiver_node_id }) = payment {
-                                               self.pending_events.lock().unwrap().push(events::Event::PaymentClaimed {
+                                               self.pending_events.lock().unwrap().push_back((events::Event::PaymentClaimed {
                                                        payment_hash, purpose, amount_msat, receiver_node_id: Some(receiver_node_id),
-                                               });
+                                               }, None));
                                        }
                                },
-                               MonitorUpdateCompletionAction::EmitEvent { event } => {
-                                       self.pending_events.lock().unwrap().push(event);
+                               MonitorUpdateCompletionAction::EmitEventAndFreeOtherChannel {
+                                       event, downstream_counterparty_and_funding_outpoint
+                               } => {
+                                       self.pending_events.lock().unwrap().push_back((event, None));
+                                       if let Some((node_id, funding_outpoint, blocker)) = downstream_counterparty_and_funding_outpoint {
+                                               self.handle_monitor_update_release(node_id, funding_outpoint, Some(blocker));
+                                       }
                                },
                        }
                }
@@ -4227,7 +4779,7 @@ where
                channel_ready: Option<msgs::ChannelReady>, announcement_sigs: Option<msgs::AnnouncementSignatures>)
        -> Option<(u64, OutPoint, u128, Vec<(PendingHTLCInfo, u64)>)> {
                log_trace!(self.logger, "Handling channel resumption for channel {} with {} RAA, {} commitment update, {} pending forwards, {}broadcasting funding, {} channel ready, {} announcement",
-                       log_bytes!(channel.channel_id()),
+                       log_bytes!(channel.context.channel_id()),
                        if raa.is_some() { "an" } else { "no" },
                        if commitment_update.is_some() { "a" } else { "no" }, pending_forwards.len(),
                        if funding_broadcastable.is_some() { "" } else { "not " },
@@ -4236,10 +4788,10 @@ where
 
                let mut htlc_forwards = None;
 
-               let counterparty_node_id = channel.get_counterparty_node_id();
+               let counterparty_node_id = channel.context.get_counterparty_node_id();
                if !pending_forwards.is_empty() {
-                       htlc_forwards = Some((channel.get_short_channel_id().unwrap_or(channel.outbound_scid_alias()),
-                               channel.get_funding_txo().unwrap(), channel.get_user_id(), pending_forwards));
+                       htlc_forwards = Some((channel.context.get_short_channel_id().unwrap_or(channel.context.outbound_scid_alias()),
+                               channel.context.get_funding_txo().unwrap(), channel.context.get_user_id(), pending_forwards));
                }
 
                if let Some(msg) = channel_ready {
@@ -4252,8 +4804,6 @@ where
                        });
                }
 
-               emit_channel_ready_event!(self, channel);
-
                macro_rules! handle_cs { () => {
                        if let Some(update) = commitment_update {
                                pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
@@ -4283,7 +4833,13 @@ where
 
                if let Some(tx) = funding_broadcastable {
                        log_info!(self.logger, "Broadcasting funding transaction with txid {}", tx.txid());
-                       self.tx_broadcaster.broadcast_transaction(&tx);
+                       self.tx_broadcaster.broadcast_transactions(&[&tx]);
+               }
+
+               {
+                       let mut pending_events = self.pending_events.lock().unwrap();
+                       emit_channel_pending_event!(pending_events, channel);
+                       emit_channel_ready_event!(pending_events, channel);
                }
 
                htlc_forwards
@@ -4317,8 +4873,8 @@ where
                        }
                };
                log_trace!(self.logger, "ChannelMonitor updated to {}. Current highest is {}",
-                       highest_applied_update_id, channel.get().get_latest_monitor_update_id());
-               if !channel.get().is_awaiting_monitor_update() || channel.get().get_latest_monitor_update_id() != highest_applied_update_id {
+                       highest_applied_update_id, channel.get().context.get_latest_monitor_update_id());
+               if !channel.get().is_awaiting_monitor_update() || channel.get().context.get_latest_monitor_update_id() != highest_applied_update_id {
                        return;
                }
                handle_monitor_update_completion!(self, highest_applied_update_id, peer_state_lock, peer_state, per_peer_state, channel.get_mut());
@@ -4367,25 +4923,26 @@ where
        }
 
        fn do_accept_inbound_channel(&self, temporary_channel_id: &[u8; 32], counterparty_node_id: &PublicKey, accept_0conf: bool, user_channel_id: u128) -> Result<(), APIError> {
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
 
-               let peers_without_funded_channels = self.peers_without_funded_channels(|peer| !peer.channel_by_id.is_empty());
+               let peers_without_funded_channels =
+                       self.peers_without_funded_channels(|peer| { peer.total_channel_count() > 0 });
                let per_peer_state = self.per_peer_state.read().unwrap();
                let peer_state_mutex = per_peer_state.get(counterparty_node_id)
                        .ok_or_else(|| APIError::ChannelUnavailable { err: format!("Can't find a peer matching the passed counterparty node_id {}", counterparty_node_id) })?;
                let mut peer_state_lock = peer_state_mutex.lock().unwrap();
                let peer_state = &mut *peer_state_lock;
-               let is_only_peer_channel = peer_state.channel_by_id.len() == 1;
-               match peer_state.channel_by_id.entry(temporary_channel_id.clone()) {
+               let is_only_peer_channel = peer_state.total_channel_count() == 1;
+               match peer_state.inbound_v1_channel_by_id.entry(temporary_channel_id.clone()) {
                        hash_map::Entry::Occupied(mut channel) => {
-                               if !channel.get().inbound_is_awaiting_accept() {
+                               if !channel.get().is_awaiting_accept() {
                                        return Err(APIError::APIMisuseError { err: "The channel isn't currently awaiting to be accepted.".to_owned() });
                                }
                                if accept_0conf {
                                        channel.get_mut().set_0conf();
-                               } else if channel.get().get_channel_type().requires_zero_conf() {
+                               } else if channel.get().context.get_channel_type().requires_zero_conf() {
                                        let send_msg_err_event = events::MessageSendEvent::HandleError {
-                                               node_id: channel.get().get_counterparty_node_id(),
+                                               node_id: channel.get().context.get_counterparty_node_id(),
                                                action: msgs::ErrorAction::SendErrorMessage{
                                                        msg: msgs::ErrorMessage { channel_id: temporary_channel_id.clone(), data: "No zero confirmation channels accepted".to_owned(), }
                                                }
@@ -4399,7 +4956,7 @@ where
                                        // channels per-peer we can accept channels from a peer with existing ones.
                                        if is_only_peer_channel && peers_without_funded_channels >= MAX_UNFUNDED_CHANNEL_PEERS {
                                                let send_msg_err_event = events::MessageSendEvent::HandleError {
-                                                       node_id: channel.get().get_counterparty_node_id(),
+                                                       node_id: channel.get().context.get_counterparty_node_id(),
                                                        action: msgs::ErrorAction::SendErrorMessage{
                                                                msg: msgs::ErrorMessage { channel_id: temporary_channel_id.clone(), data: "Have too many peers with unfunded channels, not accepting new ones".to_owned(), }
                                                        }
@@ -4411,7 +4968,7 @@ where
                                }
 
                                peer_state.pending_msg_events.push(events::MessageSendEvent::SendAcceptChannel {
-                                       node_id: channel.get().get_counterparty_node_id(),
+                                       node_id: channel.get().context.get_counterparty_node_id(),
                                        msg: channel.get_mut().accept_inbound_channel(user_channel_id),
                                });
                        }
@@ -4437,7 +4994,7 @@ where
                                let peer = peer_mtx.lock().unwrap();
                                if !maybe_count_peer(&*peer) { continue; }
                                let num_unfunded_channels = Self::unfunded_channel_count(&peer, best_block_height);
-                               if num_unfunded_channels == peer.channel_by_id.len() {
+                               if num_unfunded_channels == peer.total_channel_count() {
                                        peers_without_funded_channels += 1;
                                }
                        }
@@ -4450,12 +5007,19 @@ where
        ) -> usize {
                let mut num_unfunded_channels = 0;
                for (_, chan) in peer.channel_by_id.iter() {
-                       if !chan.is_outbound() && chan.minimum_depth().unwrap_or(1) != 0 &&
-                               chan.get_funding_tx_confirmations(best_block_height) == 0
+                       // This covers non-zero-conf inbound `Channel`s that we are currently monitoring, but those
+                       // which have not yet had any confirmations on-chain.
+                       if !chan.context.is_outbound() && chan.context.minimum_depth().unwrap_or(1) != 0 &&
+                               chan.context.get_funding_tx_confirmations(best_block_height) == 0
                        {
                                num_unfunded_channels += 1;
                        }
                }
+               for (_, chan) in peer.inbound_v1_channel_by_id.iter() {
+                       if chan.context.minimum_depth().unwrap_or(1) != 0 {
+                               num_unfunded_channels += 1;
+                       }
+               }
                num_unfunded_channels
        }
 
@@ -4476,7 +5040,8 @@ where
                // Get the number of peers with channels, but without funded ones. We don't care too much
                // about peers that never open a channel, so we filter by peers that have at least one
                // channel, and then limit the number of those with unfunded channels.
-               let channeled_peers_without_funding = self.peers_without_funded_channels(|node| !node.channel_by_id.is_empty());
+               let channeled_peers_without_funding =
+                       self.peers_without_funded_channels(|node| node.total_channel_count() > 0);
 
                let per_peer_state = self.per_peer_state.read().unwrap();
                let peer_state_mutex = per_peer_state.get(counterparty_node_id)
@@ -4490,7 +5055,7 @@ where
                // If this peer already has some channels, a new channel won't increase our number of peers
                // with unfunded channels, so as long as we aren't over the maximum number of unfunded
                // channels per-peer we can accept channels from a peer with existing ones.
-               if peer_state.channel_by_id.is_empty() &&
+               if peer_state.total_channel_count() == 0 &&
                        channeled_peers_without_funding >= MAX_UNFUNDED_CHANNEL_PEERS &&
                        !self.default_configuration.manually_accept_inbound_channels
                {
@@ -4506,7 +5071,7 @@ where
                                msg.temporary_channel_id.clone()));
                }
 
-               let mut channel = match Channel::new_from_req(&self.fee_estimator, &self.entropy_source, &self.signer_provider,
+               let mut channel = match InboundV1Channel::new(&self.fee_estimator, &self.entropy_source, &self.signer_provider,
                        counterparty_node_id.clone(), &self.channel_type_features(), &peer_state.latest_features, msg, user_channel_id,
                        &self.default_configuration, best_block_height, &self.logger, outbound_scid_alias)
                {
@@ -4516,35 +5081,31 @@ where
                        },
                        Ok(res) => res
                };
-               match peer_state.channel_by_id.entry(channel.channel_id()) {
-                       hash_map::Entry::Occupied(_) => {
-                               self.outbound_scid_aliases.lock().unwrap().remove(&outbound_scid_alias);
-                               return Err(MsgHandleErrInternal::send_err_msg_no_close("temporary_channel_id collision for the same peer!".to_owned(), msg.temporary_channel_id.clone()))
-                       },
-                       hash_map::Entry::Vacant(entry) => {
-                               if !self.default_configuration.manually_accept_inbound_channels {
-                                       if channel.get_channel_type().requires_zero_conf() {
-                                               return Err(MsgHandleErrInternal::send_err_msg_no_close("No zero confirmation channels accepted".to_owned(), msg.temporary_channel_id.clone()));
-                                       }
-                                       peer_state.pending_msg_events.push(events::MessageSendEvent::SendAcceptChannel {
-                                               node_id: counterparty_node_id.clone(),
-                                               msg: channel.accept_inbound_channel(user_channel_id),
-                                       });
-                               } else {
-                                       let mut pending_events = self.pending_events.lock().unwrap();
-                                       pending_events.push(
-                                               events::Event::OpenChannelRequest {
-                                                       temporary_channel_id: msg.temporary_channel_id.clone(),
-                                                       counterparty_node_id: counterparty_node_id.clone(),
-                                                       funding_satoshis: msg.funding_satoshis,
-                                                       push_msat: msg.push_msat,
-                                                       channel_type: channel.get_channel_type().clone(),
-                                               }
-                                       );
+               let channel_id = channel.context.channel_id();
+               let channel_exists = peer_state.has_channel(&channel_id);
+               if channel_exists {
+                       self.outbound_scid_aliases.lock().unwrap().remove(&outbound_scid_alias);
+                       return Err(MsgHandleErrInternal::send_err_msg_no_close("temporary_channel_id collision for the same peer!".to_owned(), msg.temporary_channel_id.clone()))
+               } else {
+                       if !self.default_configuration.manually_accept_inbound_channels {
+                               if channel.context.get_channel_type().requires_zero_conf() {
+                                       return Err(MsgHandleErrInternal::send_err_msg_no_close("No zero confirmation channels accepted".to_owned(), msg.temporary_channel_id.clone()));
                                }
-
-                               entry.insert(channel);
+                               peer_state.pending_msg_events.push(events::MessageSendEvent::SendAcceptChannel {
+                                       node_id: counterparty_node_id.clone(),
+                                       msg: channel.accept_inbound_channel(user_channel_id),
+                               });
+                       } else {
+                               let mut pending_events = self.pending_events.lock().unwrap();
+                               pending_events.push_back((events::Event::OpenChannelRequest {
+                                       temporary_channel_id: msg.temporary_channel_id.clone(),
+                                       counterparty_node_id: counterparty_node_id.clone(),
+                                       funding_satoshis: msg.funding_satoshis,
+                                       push_msat: msg.push_msat,
+                                       channel_type: channel.context.get_channel_type().clone(),
+                               }, None));
                        }
+                       peer_state.inbound_v1_channel_by_id.insert(channel_id, channel);
                }
                Ok(())
        }
@@ -4559,22 +5120,22 @@ where
                                })?;
                        let mut peer_state_lock = peer_state_mutex.lock().unwrap();
                        let peer_state = &mut *peer_state_lock;
-                       match peer_state.channel_by_id.entry(msg.temporary_channel_id) {
+                       match peer_state.outbound_v1_channel_by_id.entry(msg.temporary_channel_id) {
                                hash_map::Entry::Occupied(mut chan) => {
-                                       try_chan_entry!(self, chan.get_mut().accept_channel(&msg, &self.default_configuration.channel_handshake_limits, &peer_state.latest_features), chan);
-                                       (chan.get().get_value_satoshis(), chan.get().get_funding_redeemscript().to_v0_p2wsh(), chan.get().get_user_id())
+                                       try_v1_outbound_chan_entry!(self, chan.get_mut().accept_channel(&msg, &self.default_configuration.channel_handshake_limits, &peer_state.latest_features), chan);
+                                       (chan.get().context.get_value_satoshis(), chan.get().context.get_funding_redeemscript().to_v0_p2wsh(), chan.get().context.get_user_id())
                                },
                                hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close(format!("Got a message for a channel from the wrong node! No such channel for the passed counterparty_node_id {}", counterparty_node_id), msg.temporary_channel_id))
                        }
                };
                let mut pending_events = self.pending_events.lock().unwrap();
-               pending_events.push(events::Event::FundingGenerationReady {
+               pending_events.push_back((events::Event::FundingGenerationReady {
                        temporary_channel_id: msg.temporary_channel_id,
                        counterparty_node_id: *counterparty_node_id,
                        channel_value_satoshis: value,
                        output_script,
                        user_channel_id: user_id,
-               });
+               }, None));
                Ok(())
        }
 
@@ -4590,12 +5151,24 @@ where
 
                let mut peer_state_lock = peer_state_mutex.lock().unwrap();
                let peer_state = &mut *peer_state_lock;
-               let ((funding_msg, monitor), chan) =
-                       match peer_state.channel_by_id.entry(msg.temporary_channel_id) {
-                               hash_map::Entry::Occupied(mut chan) => {
-                                       (try_chan_entry!(self, chan.get_mut().funding_created(msg, best_block, &self.signer_provider, &self.logger), chan), chan.remove())
+               let (chan, funding_msg, monitor) =
+                       match peer_state.inbound_v1_channel_by_id.remove(&msg.temporary_channel_id) {
+                               Some(inbound_chan) => {
+                                       match inbound_chan.funding_created(msg, best_block, &self.signer_provider, &self.logger) {
+                                               Ok(res) => res,
+                                               Err((mut inbound_chan, err)) => {
+                                                       // We've already removed this inbound channel from the map in `PeerState`
+                                                       // above so at this point we just need to clean up any lingering entries
+                                                       // concerning this channel as it is safe to do so.
+                                                       update_maps_on_chan_removal!(self, &inbound_chan.context);
+                                                       let user_id = inbound_chan.context.get_user_id();
+                                                       let shutdown_res = inbound_chan.context.force_shutdown(false);
+                                                       return Err(MsgHandleErrInternal::from_finish_shutdown(format!("{}", err),
+                                                               msg.temporary_channel_id, user_id, shutdown_res, None));
+                                               },
+                                       }
                                },
-                               hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close(format!("Got a message for a channel from the wrong node! No such channel for the passed counterparty_node_id {}", counterparty_node_id), msg.temporary_channel_id))
+                               None => return Err(MsgHandleErrInternal::send_err_msg_no_close(format!("Got a message for a channel from the wrong node! No such channel for the passed counterparty_node_id {}", counterparty_node_id), msg.temporary_channel_id))
                        };
 
                match peer_state.channel_by_id.entry(funding_msg.channel_id) {
@@ -4603,14 +5176,14 @@ where
                                Err(MsgHandleErrInternal::send_err_msg_no_close("Already had channel with the new channel_id".to_owned(), funding_msg.channel_id))
                        },
                        hash_map::Entry::Vacant(e) => {
-                               match self.id_to_peer.lock().unwrap().entry(chan.channel_id()) {
+                               match self.id_to_peer.lock().unwrap().entry(chan.context.channel_id()) {
                                        hash_map::Entry::Occupied(_) => {
                                                return Err(MsgHandleErrInternal::send_err_msg_no_close(
                                                        "The funding_created message had the same funding_txid as an existing channel - funding is not possible".to_owned(),
                                                        funding_msg.channel_id))
                                        },
                                        hash_map::Entry::Vacant(i_e) => {
-                                               i_e.insert(chan.get_counterparty_node_id());
+                                               i_e.insert(chan.context.get_counterparty_node_id());
                                        }
                                }
 
@@ -4660,7 +5233,7 @@ where
                        hash_map::Entry::Occupied(mut chan) => {
                                let monitor = try_chan_entry!(self,
                                        chan.get_mut().funding_signed(&msg, best_block, &self.signer_provider, &self.logger), chan);
-                               let update_res = self.chain_monitor.watch_channel(chan.get().get_funding_txo().unwrap(), monitor);
+                               let update_res = self.chain_monitor.watch_channel(chan.get().context.get_funding_txo().unwrap(), monitor);
                                let mut res = handle_new_monitor_update!(self, update_res, 0, peer_state_lock, peer_state, per_peer_state, chan);
                                if let Err(MsgHandleErrInternal { ref mut shutdown_finish, .. }) = res {
                                        // We weren't able to watch the channel to begin with, so no updates should be made on
@@ -4690,18 +5263,18 @@ where
                                let announcement_sigs_opt = try_chan_entry!(self, chan.get_mut().channel_ready(&msg, &self.node_signer,
                                        self.genesis_hash.clone(), &self.default_configuration, &self.best_block.read().unwrap(), &self.logger), chan);
                                if let Some(announcement_sigs) = announcement_sigs_opt {
-                                       log_trace!(self.logger, "Sending announcement_signatures for channel {}", log_bytes!(chan.get().channel_id()));
+                                       log_trace!(self.logger, "Sending announcement_signatures for channel {}", log_bytes!(chan.get().context.channel_id()));
                                        peer_state.pending_msg_events.push(events::MessageSendEvent::SendAnnouncementSignatures {
                                                node_id: counterparty_node_id.clone(),
                                                msg: announcement_sigs,
                                        });
-                               } else if chan.get().is_usable() {
+                               } else if chan.get().context.is_usable() {
                                        // If we're sending an announcement_signatures, we'll send the (public)
                                        // channel_update after sending a channel_announcement when we receive our
                                        // counterparty's announcement_signatures. Thus, we only bother to send a
                                        // channel_update here if the channel is not public, i.e. we're not sending an
                                        // announcement_signatures.
-                                       log_trace!(self.logger, "Sending private initial channel_update for our counterparty on channel {}", log_bytes!(chan.get().channel_id()));
+                                       log_trace!(self.logger, "Sending private initial channel_update for our counterparty on channel {}", log_bytes!(chan.get().context.channel_id()));
                                        if let Ok(msg) = self.get_channel_update_for_unicast(chan.get()) {
                                                peer_state.pending_msg_events.push(events::MessageSendEvent::SendChannelUpdate {
                                                        node_id: counterparty_node_id.clone(),
@@ -4710,7 +5283,10 @@ where
                                        }
                                }
 
-                               emit_channel_ready_event!(self, chan.get_mut());
+                               {
+                                       let mut pending_events = self.pending_events.lock().unwrap();
+                                       emit_channel_ready_event!(pending_events, chan.get_mut());
+                               }
 
                                Ok(())
                        },
@@ -4738,7 +5314,7 @@ where
                                                        if chan_entry.get().sent_shutdown() { " after we initiated shutdown" } else { "" });
                                        }
 
-                                       let funding_txo_opt = chan_entry.get().get_funding_txo();
+                                       let funding_txo_opt = chan_entry.get().context.get_funding_txo();
                                        let (shutdown, monitor_update_opt, htlcs) = try_chan_entry!(self,
                                                chan_entry.get_mut().shutdown(&self.signer_provider, &peer_state.latest_features, &msg), chan_entry);
                                        dropped_htlcs = htlcs;
@@ -4806,7 +5382,7 @@ where
                };
                if let Some(broadcast_tx) = tx {
                        log_info!(self.logger, "Broadcasting {}", log_tx!(broadcast_tx));
-                       self.tx_broadcaster.broadcast_transaction(&broadcast_tx);
+                       self.tx_broadcaster.broadcast_transactions(&[&broadcast_tx]);
                }
                if let Some(chan) = chan_option {
                        if let Ok(update) = self.get_channel_update_for_broadcast(&chan) {
@@ -4816,7 +5392,7 @@ where
                                        msg: update
                                });
                        }
-                       self.issue_channel_close_events(&chan, ClosureReason::CooperativeClosure);
+                       self.issue_channel_close_events(&chan.context, ClosureReason::CooperativeClosure);
                }
                Ok(())
        }
@@ -4831,7 +5407,7 @@ where
                //encrypted with the same key. It's not immediately obvious how to usefully exploit that,
                //but we should prevent it anyway.
 
-               let pending_forward_info = self.decode_update_add_htlc_onion(msg);
+               let decoded_hop_res = self.decode_update_add_htlc_onion(msg);
                let per_peer_state = self.per_peer_state.read().unwrap();
                let peer_state_mutex = per_peer_state.get(counterparty_node_id)
                        .ok_or_else(|| {
@@ -4843,6 +5419,11 @@ where
                match peer_state.channel_by_id.entry(msg.channel_id) {
                        hash_map::Entry::Occupied(mut chan) => {
 
+                               let pending_forward_info = match decoded_hop_res {
+                                       Ok((next_hop, shared_secret, next_packet_pk_opt)) =>
+                                               self.construct_pending_htlc_status(msg, shared_secret, next_hop, next_packet_pk_opt),
+                                       Err(e) => PendingHTLCStatus::Fail(e)
+                               };
                                let create_pending_htlc_status = |chan: &Channel<<SP::Target as SignerProvider>::Signer>, pending_forward_info: PendingHTLCStatus, error_code: u16| {
                                        // If the update_add is completely bogus, the call will Err and we will close,
                                        // but if we've sent a shutdown and they haven't acknowledged it yet, we just
@@ -4944,12 +5525,14 @@ where
                let peer_state = &mut *peer_state_lock;
                match peer_state.channel_by_id.entry(msg.channel_id) {
                        hash_map::Entry::Occupied(mut chan) => {
-                               let funding_txo = chan.get().get_funding_txo();
-                               let monitor_update = try_chan_entry!(self, chan.get_mut().commitment_signed(&msg, &self.logger), chan);
-                               let update_res = self.chain_monitor.update_channel(funding_txo.unwrap(), monitor_update);
-                               let update_id = monitor_update.update_id;
-                               handle_new_monitor_update!(self, update_res, update_id, peer_state_lock,
-                                       peer_state, per_peer_state, chan)
+                               let funding_txo = chan.get().context.get_funding_txo();
+                               let monitor_update_opt = try_chan_entry!(self, chan.get_mut().commitment_signed(&msg, &self.logger), chan);
+                               if let Some(monitor_update) = monitor_update_opt {
+                                       let update_res = self.chain_monitor.update_channel(funding_txo.unwrap(), monitor_update);
+                                       let update_id = monitor_update.update_id;
+                                       handle_new_monitor_update!(self, update_res, update_id, peer_state_lock,
+                                               peer_state, per_peer_state, chan)
+                               } else { Ok(()) }
                        },
                        hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close(format!("Got a message for a channel from the wrong node! No such channel for the passed counterparty_node_id {}", counterparty_node_id), msg.channel_id))
                }
@@ -4959,7 +5542,7 @@ where
        fn forward_htlcs(&self, per_source_pending_forwards: &mut [(u64, OutPoint, u128, Vec<(PendingHTLCInfo, u64)>)]) {
                for &mut (prev_short_channel_id, prev_funding_outpoint, prev_user_channel_id, ref mut pending_forwards) in per_source_pending_forwards {
                        let mut push_forward_event = false;
-                       let mut new_intercept_events = Vec::new();
+                       let mut new_intercept_events = VecDeque::new();
                        let mut failed_intercept_forwards = Vec::new();
                        if !pending_forwards.is_empty() {
                                for (forward_info, prev_htlc_id) in pending_forwards.drain(..) {
@@ -4986,13 +5569,13 @@ where
                                                                let mut pending_intercepts = self.pending_intercepted_htlcs.lock().unwrap();
                                                                match pending_intercepts.entry(intercept_id) {
                                                                        hash_map::Entry::Vacant(entry) => {
-                                                                               new_intercept_events.push(events::Event::HTLCIntercepted {
+                                                                               new_intercept_events.push_back((events::Event::HTLCIntercepted {
                                                                                        requested_next_hop_scid: scid,
                                                                                        payment_hash: forward_info.payment_hash,
                                                                                        inbound_amount_msat: forward_info.incoming_amt_msat.unwrap(),
                                                                                        expected_outbound_amount_msat: forward_info.outgoing_amt_msat,
                                                                                        intercept_id
-                                                                               });
+                                                                               }, None));
                                                                                entry.insert(PendingAddHTLCInfo {
                                                                                        prev_short_channel_id, prev_funding_outpoint, prev_htlc_id, prev_user_channel_id, forward_info });
                                                                        },
@@ -5042,14 +5625,32 @@ where
        fn push_pending_forwards_ev(&self) {
                let mut pending_events = self.pending_events.lock().unwrap();
                let forward_ev_exists = pending_events.iter()
-                       .find(|ev| if let events::Event::PendingHTLCsForwardable { .. } = ev { true } else { false })
+                       .find(|(ev, _)| if let events::Event::PendingHTLCsForwardable { .. } = ev { true } else { false })
                        .is_some();
                if !forward_ev_exists {
-                       pending_events.push(events::Event::PendingHTLCsForwardable {
+                       pending_events.push_back((events::Event::PendingHTLCsForwardable {
                                time_forwardable:
                                        Duration::from_millis(MIN_HTLC_RELAY_HOLDING_CELL_MILLIS),
-                       });
-               }
+                       }, None));
+               }
+       }
+
+       /// Checks whether [`ChannelMonitorUpdate`]s generated by the receipt of a remote
+       /// [`msgs::RevokeAndACK`] should be held for the given channel until some other event
+       /// completes. Note that this needs to happen in the same [`PeerState`] mutex as any release of
+       /// the [`ChannelMonitorUpdate`] in question.
+       fn raa_monitor_updates_held(&self,
+               actions_blocking_raa_monitor_updates: &BTreeMap<[u8; 32], Vec<RAAMonitorUpdateBlockingAction>>,
+               channel_funding_outpoint: OutPoint, counterparty_node_id: PublicKey
+       ) -> bool {
+               actions_blocking_raa_monitor_updates
+                       .get(&channel_funding_outpoint.to_channel_id()).map(|v| !v.is_empty()).unwrap_or(false)
+               || self.pending_events.lock().unwrap().iter().any(|(_, action)| {
+                       action == &Some(EventCompletionAction::ReleaseRAAChannelMonitorUpdate {
+                               channel_funding_outpoint,
+                               counterparty_node_id,
+                       })
+               })
        }
 
        fn internal_revoke_and_ack(&self, counterparty_node_id: &PublicKey, msg: &msgs::RevokeAndACK) -> Result<(), MsgHandleErrInternal> {
@@ -5063,12 +5664,14 @@ where
                        let peer_state = &mut *peer_state_lock;
                        match peer_state.channel_by_id.entry(msg.channel_id) {
                                hash_map::Entry::Occupied(mut chan) => {
-                                       let funding_txo = chan.get().get_funding_txo();
-                                       let (htlcs_to_fail, monitor_update) = try_chan_entry!(self, chan.get_mut().revoke_and_ack(&msg, &self.logger), chan);
-                                       let update_res = self.chain_monitor.update_channel(funding_txo.unwrap(), monitor_update);
-                                       let update_id = monitor_update.update_id;
-                                       let res = handle_new_monitor_update!(self, update_res, update_id,
-                                               peer_state_lock, peer_state, per_peer_state, chan);
+                                       let funding_txo = chan.get().context.get_funding_txo();
+                                       let (htlcs_to_fail, monitor_update_opt) = try_chan_entry!(self, chan.get_mut().revoke_and_ack(&msg, &self.logger), chan);
+                                       let res = if let Some(monitor_update) = monitor_update_opt {
+                                               let update_res = self.chain_monitor.update_channel(funding_txo.unwrap(), monitor_update);
+                                               let update_id = monitor_update.update_id;
+                                               handle_new_monitor_update!(self, update_res, update_id,
+                                                       peer_state_lock, peer_state, per_peer_state, chan)
+                                       } else { Ok(()) };
                                        (htlcs_to_fail, res)
                                },
                                hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close(format!("Got a message for a channel from the wrong node! No such channel for the passed counterparty_node_id {}", counterparty_node_id), msg.channel_id))
@@ -5107,7 +5710,7 @@ where
                let peer_state = &mut *peer_state_lock;
                match peer_state.channel_by_id.entry(msg.channel_id) {
                        hash_map::Entry::Occupied(mut chan) => {
-                               if !chan.get().is_usable() {
+                               if !chan.get().context.is_usable() {
                                        return Err(MsgHandleErrInternal::from_no_close(LightningError{err: "Got an announcement_signatures before we were ready for it".to_owned(), action: msgs::ErrorAction::IgnoreError}));
                                }
 
@@ -5144,8 +5747,8 @@ where
                let peer_state = &mut *peer_state_lock;
                match peer_state.channel_by_id.entry(chan_id) {
                        hash_map::Entry::Occupied(mut chan) => {
-                               if chan.get().get_counterparty_node_id() != *counterparty_node_id {
-                                       if chan.get().should_announce() {
+                               if chan.get().context.get_counterparty_node_id() != *counterparty_node_id {
+                                       if chan.get().context.should_announce() {
                                                // If the announcement is about a channel of ours which is public, some
                                                // other peer may simply be forwarding all its gossip to us. Don't provide
                                                // a scary-looking error message and return Ok instead.
@@ -5153,7 +5756,7 @@ where
                                        }
                                        return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a channel_update for a channel from the wrong node - it shouldn't know about our private channels!".to_owned(), chan_id));
                                }
-                               let were_node_one = self.get_our_node_id().serialize()[..] < chan.get().get_counterparty_node_id().serialize()[..];
+                               let were_node_one = self.get_our_node_id().serialize()[..] < chan.get().context.get_counterparty_node_id().serialize()[..];
                                let msg_from_node_one = msg.contents.flags & 1 == 0;
                                if were_node_one == msg_from_node_one {
                                        return Ok(NotifyOption::SkipPersist);
@@ -5194,18 +5797,18 @@ where
                                                        node_id: counterparty_node_id.clone(),
                                                        msg,
                                                });
-                                       } else if chan.get().is_usable() {
+                                       } else if chan.get().context.is_usable() {
                                                // If the channel is in a usable state (ie the channel is not being shut
                                                // down), send a unicast channel_update to our counterparty to make sure
                                                // they have the latest channel parameters.
                                                if let Ok(msg) = self.get_channel_update_for_unicast(chan.get()) {
                                                        channel_update = Some(events::MessageSendEvent::SendChannelUpdate {
-                                                               node_id: chan.get().get_counterparty_node_id(),
+                                                               node_id: chan.get().context.get_counterparty_node_id(),
                                                                msg,
                                                        });
                                                }
                                        }
-                                       let need_lnd_workaround = chan.get_mut().workaround_lnd_bug_4006.take();
+                                       let need_lnd_workaround = chan.get_mut().context.workaround_lnd_bug_4006.take();
                                        htlc_forwards = self.handle_channel_resumption(
                                                &mut peer_state.pending_msg_events, chan.get_mut(), responses.raa, responses.commitment_update, responses.order,
                                                Vec::new(), None, responses.channel_ready, responses.announcement_sigs);
@@ -5268,7 +5871,7 @@ where
                                                                let pending_msg_events = &mut peer_state.pending_msg_events;
                                                                if let hash_map::Entry::Occupied(chan_entry) = peer_state.channel_by_id.entry(funding_outpoint.to_channel_id()) {
                                                                        let mut chan = remove_channel!(self, chan_entry);
-                                                                       failed_channels.push(chan.force_shutdown(false));
+                                                                       failed_channels.push(chan.context.force_shutdown(false));
                                                                        if let Ok(update) = self.get_channel_update_for_broadcast(&chan) {
                                                                                pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
                                                                                        msg: update
@@ -5279,11 +5882,11 @@ where
                                                                        } else {
                                                                                ClosureReason::CommitmentTxConfirmed
                                                                        };
-                                                                       self.issue_channel_close_events(&chan, reason);
+                                                                       self.issue_channel_close_events(&chan.context, reason);
                                                                        pending_msg_events.push(events::MessageSendEvent::HandleError {
-                                                                               node_id: chan.get_counterparty_node_id(),
+                                                                               node_id: chan.context.get_counterparty_node_id(),
                                                                                action: msgs::ErrorAction::SendErrorMessage {
-                                                                                       msg: msgs::ErrorMessage { channel_id: chan.channel_id(), data: "Channel force-closed".to_owned() }
+                                                                                       msg: msgs::ErrorMessage { channel_id: chan.context.channel_id(), data: "Channel force-closed".to_owned() }
                                                                                },
                                                                        });
                                                                }
@@ -5309,13 +5912,8 @@ where
        /// update events as a separate process method here.
        #[cfg(fuzzing)]
        pub fn process_monitor_events(&self) {
-               PersistenceNotifierGuard::optionally_notify(&self.total_consistency_lock, &self.persistence_notifier, || {
-                       if self.process_pending_monitor_events() {
-                               NotifyOption::DoPersist
-                       } else {
-                               NotifyOption::SkipPersist
-                       }
-               });
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
+               self.process_pending_monitor_events();
        }
 
        /// Check the holding cell in each channel and free any pending HTLCs in them if possible.
@@ -5337,8 +5935,8 @@ where
                                        let mut peer_state_lock = peer_state_mutex.lock().unwrap();
                                        let peer_state: &mut PeerState<_> = &mut *peer_state_lock;
                                        for (channel_id, chan) in peer_state.channel_by_id.iter_mut() {
-                                               let counterparty_node_id = chan.get_counterparty_node_id();
-                                               let funding_txo = chan.get_funding_txo();
+                                               let counterparty_node_id = chan.context.get_counterparty_node_id();
+                                               let funding_txo = chan.context.get_funding_txo();
                                                let (monitor_opt, holding_cell_failed_htlcs) =
                                                        chan.maybe_free_holding_cell_htlcs(&self.logger);
                                                if !holding_cell_failed_htlcs.is_empty() {
@@ -5397,7 +5995,7 @@ where
                                                        if let Some(msg) = msg_opt {
                                                                has_update = true;
                                                                pending_msg_events.push(events::MessageSendEvent::SendClosingSigned {
-                                                                       node_id: chan.get_counterparty_node_id(), msg,
+                                                                       node_id: chan.context.get_counterparty_node_id(), msg,
                                                                });
                                                        }
                                                        if let Some(tx) = tx_opt {
@@ -5409,18 +6007,18 @@ where
                                                                        });
                                                                }
 
-                                                               self.issue_channel_close_events(chan, ClosureReason::CooperativeClosure);
+                                                               self.issue_channel_close_events(&chan.context, ClosureReason::CooperativeClosure);
 
                                                                log_info!(self.logger, "Broadcasting {}", log_tx!(tx));
-                                                               self.tx_broadcaster.broadcast_transaction(&tx);
-                                                               update_maps_on_chan_removal!(self, chan);
+                                                               self.tx_broadcaster.broadcast_transactions(&[&tx]);
+                                                               update_maps_on_chan_removal!(self, &chan.context);
                                                                false
                                                        } else { true }
                                                },
                                                Err(e) => {
                                                        has_update = true;
                                                        let (close_channel, res) = convert_chan_err!(self, e, chan, channel_id);
-                                                       handle_errors.push((chan.get_counterparty_node_id(), Err(res)));
+                                                       handle_errors.push((chan.context.get_counterparty_node_id(), Err(res)));
                                                        !close_channel
                                                }
                                        }
@@ -5447,12 +6045,15 @@ where
                        // Channel::force_shutdown tries to make us do) as we may still be in initialization,
                        // so we track the update internally and handle it when the user next calls
                        // timer_tick_occurred, guaranteeing we're running normally.
-                       if let Some((funding_txo, update)) = failure.0.take() {
+                       if let Some((counterparty_node_id, funding_txo, update)) = failure.0.take() {
                                assert_eq!(update.updates.len(), 1);
                                if let ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast } = update.updates[0] {
                                        assert!(should_broadcast);
                                } else { unreachable!(); }
-                               self.pending_background_events.lock().unwrap().push(BackgroundEvent::ClosingMonitorUpdate((funding_txo, update)));
+                               self.pending_background_events.lock().unwrap().push(
+                                       BackgroundEvent::MonitorUpdateRegeneratedOnStartup {
+                                               counterparty_node_id, funding_txo, update
+                                       });
                        }
                        self.finish_force_close_channel(failure);
                }
@@ -5467,7 +6068,7 @@ where
 
                let payment_secret = PaymentSecret(self.entropy_source.get_secure_random_bytes());
 
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
                let mut payment_secrets = self.pending_inbound_payments.lock().unwrap();
                match payment_secrets.entry(payment_hash) {
                        hash_map::Entry::Vacant(e) => {
@@ -5623,7 +6224,7 @@ where
        /// Gets a fake short channel id for use in receiving [phantom node payments]. These fake scids
        /// are used when constructing the phantom invoice's route hints.
        ///
-       /// [phantom node payments]: crate::chain::keysinterface::PhantomKeysManager
+       /// [phantom node payments]: crate::sign::PhantomKeysManager
        pub fn get_phantom_scid(&self) -> u64 {
                let best_block_height = self.best_block.read().unwrap().height();
                let short_to_chan_info = self.short_to_chan_info.read().unwrap();
@@ -5639,7 +6240,7 @@ where
 
        /// Gets route hints for use in receiving [phantom node payments].
        ///
-       /// [phantom node payments]: crate::chain::keysinterface::PhantomKeysManager
+       /// [phantom node payments]: crate::sign::PhantomKeysManager
        pub fn get_phantom_route_hints(&self) -> PhantomRouteHints {
                PhantomRouteHints {
                        channels: self.list_usable_channels(),
@@ -5697,13 +6298,13 @@ where
        #[cfg(feature = "_test_utils")]
        pub fn push_pending_event(&self, event: events::Event) {
                let mut events = self.pending_events.lock().unwrap();
-               events.push(event);
+               events.push_back((event, None));
        }
 
        #[cfg(test)]
        pub fn pop_pending_event(&self) -> Option<events::Event> {
                let mut events = self.pending_events.lock().unwrap();
-               if events.is_empty() { None } else { Some(events.remove(0)) }
+               events.pop_front().map(|(e, _)| e)
        }
 
        #[cfg(test)]
@@ -5716,37 +6317,93 @@ where
                self.pending_outbound_payments.clear_pending_payments()
        }
 
-       /// Processes any events asynchronously in the order they were generated since the last call
-       /// using the given event handler.
-       ///
-       /// See the trait-level documentation of [`EventsProvider`] for requirements.
-       pub async fn process_pending_events_async<Future: core::future::Future, H: Fn(Event) -> Future>(
-               &self, handler: H
-       ) {
-               // We'll acquire our total consistency lock until the returned future completes so that
-               // we can be sure no other persists happen while processing events.
-               let _read_guard = self.total_consistency_lock.read().unwrap();
+       /// When something which was blocking a channel from updating its [`ChannelMonitor`] (e.g. an
+       /// [`Event`] being handled) completes, this should be called to restore the channel to normal
+       /// operation. It will double-check that nothing *else* is also blocking the same channel from
+       /// making progress and then any blocked [`ChannelMonitorUpdate`]s fly.
+       fn handle_monitor_update_release(&self, counterparty_node_id: PublicKey, channel_funding_outpoint: OutPoint, mut completed_blocker: Option<RAAMonitorUpdateBlockingAction>) {
+               let mut errors = Vec::new();
+               loop {
+                       let per_peer_state = self.per_peer_state.read().unwrap();
+                       if let Some(peer_state_mtx) = per_peer_state.get(&counterparty_node_id) {
+                               let mut peer_state_lck = peer_state_mtx.lock().unwrap();
+                               let peer_state = &mut *peer_state_lck;
+
+                               if let Some(blocker) = completed_blocker.take() {
+                                       // Only do this on the first iteration of the loop.
+                                       if let Some(blockers) = peer_state.actions_blocking_raa_monitor_updates
+                                               .get_mut(&channel_funding_outpoint.to_channel_id())
+                                       {
+                                               blockers.retain(|iter| iter != &blocker);
+                                       }
+                               }
 
-               let mut result = NotifyOption::SkipPersist;
+                               if self.raa_monitor_updates_held(&peer_state.actions_blocking_raa_monitor_updates,
+                                       channel_funding_outpoint, counterparty_node_id) {
+                                       // Check that, while holding the peer lock, we don't have anything else
+                                       // blocking monitor updates for this channel. If we do, release the monitor
+                                       // update(s) when those blockers complete.
+                                       log_trace!(self.logger, "Delaying monitor unlock for channel {} as another channel's mon update needs to complete first",
+                                               log_bytes!(&channel_funding_outpoint.to_channel_id()[..]));
+                                       break;
+                               }
 
-               // TODO: This behavior should be documented. It's unintuitive that we query
-               // ChannelMonitors when clearing other events.
-               if self.process_pending_monitor_events() {
-                       result = NotifyOption::DoPersist;
+                               if let hash_map::Entry::Occupied(mut chan) = peer_state.channel_by_id.entry(channel_funding_outpoint.to_channel_id()) {
+                                       debug_assert_eq!(chan.get().context.get_funding_txo().unwrap(), channel_funding_outpoint);
+                                       if let Some((monitor_update, further_update_exists)) = chan.get_mut().unblock_next_blocked_monitor_update() {
+                                               log_debug!(self.logger, "Unlocking monitor updating for channel {} and updating monitor",
+                                                       log_bytes!(&channel_funding_outpoint.to_channel_id()[..]));
+                                               let update_res = self.chain_monitor.update_channel(channel_funding_outpoint, monitor_update);
+                                               let update_id = monitor_update.update_id;
+                                               if let Err(e) = handle_new_monitor_update!(self, update_res, update_id,
+                                                       peer_state_lck, peer_state, per_peer_state, chan)
+                                               {
+                                                       errors.push((e, counterparty_node_id));
+                                               }
+                                               if further_update_exists {
+                                                       // If there are more `ChannelMonitorUpdate`s to process, restart at the
+                                                       // top of the loop.
+                                                       continue;
+                                               }
+                                       } else {
+                                               log_trace!(self.logger, "Unlocked monitor updating for channel {} without monitors to update",
+                                                       log_bytes!(&channel_funding_outpoint.to_channel_id()[..]));
+                                       }
+                               }
+                       } else {
+                               log_debug!(self.logger,
+                                       "Got a release post-RAA monitor update for peer {} but the channel is gone",
+                                       log_pubkey!(counterparty_node_id));
+                       }
+                       break;
                }
-
-               let pending_events = mem::replace(&mut *self.pending_events.lock().unwrap(), vec![]);
-               if !pending_events.is_empty() {
-                       result = NotifyOption::DoPersist;
+               for (err, counterparty_node_id) in errors {
+                       let res = Err::<(), _>(err);
+                       let _ = handle_error!(self, res, counterparty_node_id);
                }
+       }
 
-               for event in pending_events {
-                       handler(event).await;
+       fn handle_post_event_actions(&self, actions: Vec<EventCompletionAction>) {
+               for action in actions {
+                       match action {
+                               EventCompletionAction::ReleaseRAAChannelMonitorUpdate {
+                                       channel_funding_outpoint, counterparty_node_id
+                               } => {
+                                       self.handle_monitor_update_release(counterparty_node_id, channel_funding_outpoint, None);
+                               }
+                       }
                }
+       }
 
-               if result == NotifyOption::DoPersist {
-                       self.persistence_notifier.notify();
-               }
+       /// Processes any events asynchronously in the order they were generated since the last call
+       /// using the given event handler.
+       ///
+       /// See the trait-level documentation of [`EventsProvider`] for requirements.
+       pub async fn process_pending_events_async<Future: core::future::Future, H: Fn(Event) -> Future>(
+               &self, handler: H
+       ) {
+               let mut ev;
+               process_events_body!(self, ev, { handler(ev).await });
        }
 }
 
@@ -5777,7 +6434,7 @@ where
        fn get_and_clear_pending_msg_events(&self) -> Vec<MessageSendEvent> {
                let events = RefCell::new(Vec::new());
                PersistenceNotifierGuard::optionally_notify(&self.total_consistency_lock, &self.persistence_notifier, || {
-                       let mut result = NotifyOption::SkipPersist;
+                       let mut result = self.process_background_events();
 
                        // TODO: This behavior should be documented. It's unintuitive that we query
                        // ChannelMonitors when clearing other events.
@@ -5828,26 +6485,8 @@ where
        /// An [`EventHandler`] may safely call back to the provider in order to handle an event.
        /// However, it must not call [`Writeable::write`] as doing so would result in a deadlock.
        fn process_pending_events<H: Deref>(&self, handler: H) where H::Target: EventHandler {
-               PersistenceNotifierGuard::optionally_notify(&self.total_consistency_lock, &self.persistence_notifier, || {
-                       let mut result = NotifyOption::SkipPersist;
-
-                       // TODO: This behavior should be documented. It's unintuitive that we query
-                       // ChannelMonitors when clearing other events.
-                       if self.process_pending_monitor_events() {
-                               result = NotifyOption::DoPersist;
-                       }
-
-                       let pending_events = mem::replace(&mut *self.pending_events.lock().unwrap(), vec![]);
-                       if !pending_events.is_empty() {
-                               result = NotifyOption::DoPersist;
-                       }
-
-                       for event in pending_events {
-                               handler.handle_event(event);
-                       }
-
-                       result
-               });
+               let mut ev;
+               process_events_body!(self, ev, handler.handle_event(ev));
        }
 }
 
@@ -5876,7 +6515,8 @@ where
        }
 
        fn block_disconnected(&self, header: &BlockHeader, height: u32) {
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::optionally_notify(&self.total_consistency_lock,
+                       &self.persistence_notifier, || -> NotifyOption { NotifyOption::DoPersist });
                let new_height = height - 1;
                {
                        let mut best_block = self.best_block.write().unwrap();
@@ -5910,7 +6550,8 @@ where
                let block_hash = header.block_hash();
                log_trace!(self.logger, "{} transactions included in block {} at height {} provided", txdata.len(), block_hash, height);
 
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::optionally_notify(&self.total_consistency_lock,
+                       &self.persistence_notifier, || -> NotifyOption { NotifyOption::DoPersist });
                self.do_chain_event(Some(height), |channel| channel.transactions_confirmed(&block_hash, height, txdata, self.genesis_hash.clone(), &self.node_signer, &self.default_configuration, &self.logger)
                        .map(|(a, b)| (a, Vec::new(), b)));
 
@@ -5929,8 +6570,8 @@ where
                let block_hash = header.block_hash();
                log_trace!(self.logger, "New best block: {} at height {}", block_hash, height);
 
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
-
+               let _persistence_guard = PersistenceNotifierGuard::optionally_notify(&self.total_consistency_lock,
+                       &self.persistence_notifier, || -> NotifyOption { NotifyOption::DoPersist });
                *self.best_block.write().unwrap() = BestBlock::new(block_hash, height);
 
                self.do_chain_event(Some(height), |channel| channel.best_block_updated(height, header.time, self.genesis_hash.clone(), &self.node_signer, &self.default_configuration, &self.logger));
@@ -5964,7 +6605,7 @@ where
                        let mut peer_state_lock = peer_state_mutex.lock().unwrap();
                        let peer_state = &mut *peer_state_lock;
                        for chan in peer_state.channel_by_id.values() {
-                               if let (Some(funding_txo), Some(block_hash)) = (chan.get_funding_txo(), chan.get_funding_tx_confirmed_in()) {
+                               if let (Some(funding_txo), Some(block_hash)) = (chan.context.get_funding_txo(), chan.context.get_funding_tx_confirmed_in()) {
                                        res.push((funding_txo.txid, Some(block_hash)));
                                }
                        }
@@ -5973,9 +6614,10 @@ where
        }
 
        fn transaction_unconfirmed(&self, txid: &Txid) {
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::optionally_notify(&self.total_consistency_lock,
+                       &self.persistence_notifier, || -> NotifyOption { NotifyOption::DoPersist });
                self.do_chain_event(None, |channel| {
-                       if let Some(funding_txo) = channel.get_funding_txo() {
+                       if let Some(funding_txo) = channel.context.get_funding_txo() {
                                if funding_txo.txid == *txid {
                                        channel.funding_transaction_unconfirmed(&self.logger).map(|()| (None, Vec::new(), None))
                                } else { Ok((None, Vec::new(), None)) }
@@ -6018,29 +6660,32 @@ where
                                                for (source, payment_hash) in timed_out_pending_htlcs.drain(..) {
                                                        let (failure_code, data) = self.get_htlc_inbound_temp_fail_err_and_data(0x1000|14 /* expiry_too_soon */, &channel);
                                                        timed_out_htlcs.push((source, payment_hash, HTLCFailReason::reason(failure_code, data),
-                                                               HTLCDestination::NextHopChannel { node_id: Some(channel.get_counterparty_node_id()), channel_id: channel.channel_id() }));
+                                                               HTLCDestination::NextHopChannel { node_id: Some(channel.context.get_counterparty_node_id()), channel_id: channel.context.channel_id() }));
                                                }
                                                if let Some(channel_ready) = channel_ready_opt {
                                                        send_channel_ready!(self, pending_msg_events, channel, channel_ready);
-                                                       if channel.is_usable() {
-                                                               log_trace!(self.logger, "Sending channel_ready with private initial channel_update for our counterparty on channel {}", log_bytes!(channel.channel_id()));
+                                                       if channel.context.is_usable() {
+                                                               log_trace!(self.logger, "Sending channel_ready with private initial channel_update for our counterparty on channel {}", log_bytes!(channel.context.channel_id()));
                                                                if let Ok(msg) = self.get_channel_update_for_unicast(channel) {
                                                                        pending_msg_events.push(events::MessageSendEvent::SendChannelUpdate {
-                                                                               node_id: channel.get_counterparty_node_id(),
+                                                                               node_id: channel.context.get_counterparty_node_id(),
                                                                                msg,
                                                                        });
                                                                }
                                                        } else {
-                                                               log_trace!(self.logger, "Sending channel_ready WITHOUT channel_update for {}", log_bytes!(channel.channel_id()));
+                                                               log_trace!(self.logger, "Sending channel_ready WITHOUT channel_update for {}", log_bytes!(channel.context.channel_id()));
                                                        }
                                                }
 
-                                               emit_channel_ready_event!(self, channel);
+                                               {
+                                                       let mut pending_events = self.pending_events.lock().unwrap();
+                                                       emit_channel_ready_event!(pending_events, channel);
+                                               }
 
                                                if let Some(announcement_sigs) = announcement_sigs {
-                                                       log_trace!(self.logger, "Sending announcement_signatures for channel {}", log_bytes!(channel.channel_id()));
+                                                       log_trace!(self.logger, "Sending announcement_signatures for channel {}", log_bytes!(channel.context.channel_id()));
                                                        pending_msg_events.push(events::MessageSendEvent::SendAnnouncementSignatures {
-                                                               node_id: channel.get_counterparty_node_id(),
+                                                               node_id: channel.context.get_counterparty_node_id(),
                                                                msg: announcement_sigs,
                                                        });
                                                        if let Some(height) = height_opt {
@@ -6055,7 +6700,7 @@ where
                                                        }
                                                }
                                                if channel.is_our_channel_ready() {
-                                                       if let Some(real_scid) = channel.get_short_channel_id() {
+                                                       if let Some(real_scid) = channel.context.get_short_channel_id() {
                                                                // If we sent a 0conf channel_ready, and now have an SCID, we add it
                                                                // to the short_to_chan_info map here. Note that we check whether we
                                                                // can relay using the real SCID at relay-time (i.e.
@@ -6063,28 +6708,28 @@ where
                                                                // un-confirmed we force-close the channel, ensuring short_to_chan_info
                                                                // is always consistent.
                                                                let mut short_to_chan_info = self.short_to_chan_info.write().unwrap();
-                                                               let scid_insert = short_to_chan_info.insert(real_scid, (channel.get_counterparty_node_id(), channel.channel_id()));
-                                                               assert!(scid_insert.is_none() || scid_insert.unwrap() == (channel.get_counterparty_node_id(), channel.channel_id()),
+                                                               let scid_insert = short_to_chan_info.insert(real_scid, (channel.context.get_counterparty_node_id(), channel.context.channel_id()));
+                                                               assert!(scid_insert.is_none() || scid_insert.unwrap() == (channel.context.get_counterparty_node_id(), channel.context.channel_id()),
                                                                        "SCIDs should never collide - ensure you weren't behind by a full {} blocks when creating channels",
                                                                        fake_scid::MAX_SCID_BLOCKS_FROM_NOW);
                                                        }
                                                }
                                        } else if let Err(reason) = res {
-                                               update_maps_on_chan_removal!(self, channel);
+                                               update_maps_on_chan_removal!(self, &channel.context);
                                                // It looks like our counterparty went on-chain or funding transaction was
                                                // reorged out of the main chain. Close the channel.
-                                               failed_channels.push(channel.force_shutdown(true));
+                                               failed_channels.push(channel.context.force_shutdown(true));
                                                if let Ok(update) = self.get_channel_update_for_broadcast(&channel) {
                                                        pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
                                                                msg: update
                                                        });
                                                }
                                                let reason_message = format!("{}", reason);
-                                               self.issue_channel_close_events(channel, reason);
+                                               self.issue_channel_close_events(&channel.context, reason);
                                                pending_msg_events.push(events::MessageSendEvent::HandleError {
-                                                       node_id: channel.get_counterparty_node_id(),
+                                                       node_id: channel.context.get_counterparty_node_id(),
                                                        action: msgs::ErrorAction::SendErrorMessage { msg: msgs::ErrorMessage {
-                                                               channel_id: channel.channel_id(),
+                                                               channel_id: channel.context.channel_id(),
                                                                data: reason_message,
                                                        } },
                                                });
@@ -6096,8 +6741,8 @@ where
                }
 
                if let Some(height) = height_opt {
-                       self.claimable_payments.lock().unwrap().claimable_htlcs.retain(|payment_hash, (_, htlcs)| {
-                               htlcs.retain(|htlc| {
+                       self.claimable_payments.lock().unwrap().claimable_payments.retain(|payment_hash, payment| {
+                               payment.htlcs.retain(|htlc| {
                                        // If height is approaching the number of blocks we think it takes us to get
                                        // our commitment transaction confirmed before the HTLC expires, plus the
                                        // number of blocks we generally consider it to take to do a commitment update,
@@ -6112,7 +6757,7 @@ where
                                                false
                                        } else { true }
                                });
-                               !htlcs.is_empty() // Only retain this entry if htlcs has at least one entry.
+                               !payment.htlcs.is_empty() // Only retain this entry if htlcs has at least one entry.
                        });
 
                        let mut intercepted_htlcs = self.pending_intercepted_htlcs.lock().unwrap();
@@ -6146,34 +6791,11 @@ where
                }
        }
 
-       /// Blocks until ChannelManager needs to be persisted or a timeout is reached. It returns a bool
-       /// indicating whether persistence is necessary. Only one listener on
-       /// [`await_persistable_update`], [`await_persistable_update_timeout`], or a future returned by
-       /// [`get_persistable_update_future`] is guaranteed to be woken up.
-       ///
-       /// Note that this method is not available with the `no-std` feature.
+       /// Gets a [`Future`] that completes when this [`ChannelManager`] needs to be persisted.
        ///
-       /// [`await_persistable_update`]: Self::await_persistable_update
-       /// [`await_persistable_update_timeout`]: Self::await_persistable_update_timeout
-       /// [`get_persistable_update_future`]: Self::get_persistable_update_future
-       #[cfg(any(test, feature = "std"))]
-       pub fn await_persistable_update_timeout(&self, max_wait: Duration) -> bool {
-               self.persistence_notifier.wait_timeout(max_wait)
-       }
-
-       /// Blocks until ChannelManager needs to be persisted. Only one listener on
-       /// [`await_persistable_update`], `await_persistable_update_timeout`, or a future returned by
-       /// [`get_persistable_update_future`] is guaranteed to be woken up.
+       /// Note that callbacks registered on the [`Future`] MUST NOT call back into this
+       /// [`ChannelManager`] and should instead register actions to be taken later.
        ///
-       /// [`await_persistable_update`]: Self::await_persistable_update
-       /// [`get_persistable_update_future`]: Self::get_persistable_update_future
-       pub fn await_persistable_update(&self) {
-               self.persistence_notifier.wait()
-       }
-
-       /// Gets a [`Future`] that completes when a persistable update is available. Note that
-       /// callbacks registered on the [`Future`] MUST NOT call back into this [`ChannelManager`] and
-       /// should instead register actions to be taken later.
        pub fn get_persistable_update_future(&self) -> Future {
                self.persistence_notifier.get_future()
        }
@@ -6237,84 +6859,97 @@ where
        L::Target: Logger,
 {
        fn handle_open_channel(&self, counterparty_node_id: &PublicKey, msg: &msgs::OpenChannel) {
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
                let _ = handle_error!(self, self.internal_open_channel(counterparty_node_id, msg), *counterparty_node_id);
        }
 
+       fn handle_open_channel_v2(&self, counterparty_node_id: &PublicKey, msg: &msgs::OpenChannelV2) {
+               let _: Result<(), _> = handle_error!(self, Err(MsgHandleErrInternal::send_err_msg_no_close(
+                       "Dual-funded channels not supported".to_owned(),
+                        msg.temporary_channel_id.clone())), *counterparty_node_id);
+       }
+
        fn handle_accept_channel(&self, counterparty_node_id: &PublicKey, msg: &msgs::AcceptChannel) {
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
                let _ = handle_error!(self, self.internal_accept_channel(counterparty_node_id, msg), *counterparty_node_id);
        }
 
+       fn handle_accept_channel_v2(&self, counterparty_node_id: &PublicKey, msg: &msgs::AcceptChannelV2) {
+               let _: Result<(), _> = handle_error!(self, Err(MsgHandleErrInternal::send_err_msg_no_close(
+                       "Dual-funded channels not supported".to_owned(),
+                        msg.temporary_channel_id.clone())), *counterparty_node_id);
+       }
+
        fn handle_funding_created(&self, counterparty_node_id: &PublicKey, msg: &msgs::FundingCreated) {
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
                let _ = handle_error!(self, self.internal_funding_created(counterparty_node_id, msg), *counterparty_node_id);
        }
 
        fn handle_funding_signed(&self, counterparty_node_id: &PublicKey, msg: &msgs::FundingSigned) {
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
                let _ = handle_error!(self, self.internal_funding_signed(counterparty_node_id, msg), *counterparty_node_id);
        }
 
        fn handle_channel_ready(&self, counterparty_node_id: &PublicKey, msg: &msgs::ChannelReady) {
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
                let _ = handle_error!(self, self.internal_channel_ready(counterparty_node_id, msg), *counterparty_node_id);
        }
 
        fn handle_shutdown(&self, counterparty_node_id: &PublicKey, msg: &msgs::Shutdown) {
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
                let _ = handle_error!(self, self.internal_shutdown(counterparty_node_id, msg), *counterparty_node_id);
        }
 
        fn handle_closing_signed(&self, counterparty_node_id: &PublicKey, msg: &msgs::ClosingSigned) {
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
                let _ = handle_error!(self, self.internal_closing_signed(counterparty_node_id, msg), *counterparty_node_id);
        }
 
        fn handle_update_add_htlc(&self, counterparty_node_id: &PublicKey, msg: &msgs::UpdateAddHTLC) {
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
                let _ = handle_error!(self, self.internal_update_add_htlc(counterparty_node_id, msg), *counterparty_node_id);
        }
 
        fn handle_update_fulfill_htlc(&self, counterparty_node_id: &PublicKey, msg: &msgs::UpdateFulfillHTLC) {
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
                let _ = handle_error!(self, self.internal_update_fulfill_htlc(counterparty_node_id, msg), *counterparty_node_id);
        }
 
        fn handle_update_fail_htlc(&self, counterparty_node_id: &PublicKey, msg: &msgs::UpdateFailHTLC) {
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
                let _ = handle_error!(self, self.internal_update_fail_htlc(counterparty_node_id, msg), *counterparty_node_id);
        }
 
        fn handle_update_fail_malformed_htlc(&self, counterparty_node_id: &PublicKey, msg: &msgs::UpdateFailMalformedHTLC) {
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
                let _ = handle_error!(self, self.internal_update_fail_malformed_htlc(counterparty_node_id, msg), *counterparty_node_id);
        }
 
        fn handle_commitment_signed(&self, counterparty_node_id: &PublicKey, msg: &msgs::CommitmentSigned) {
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
                let _ = handle_error!(self, self.internal_commitment_signed(counterparty_node_id, msg), *counterparty_node_id);
        }
 
        fn handle_revoke_and_ack(&self, counterparty_node_id: &PublicKey, msg: &msgs::RevokeAndACK) {
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
                let _ = handle_error!(self, self.internal_revoke_and_ack(counterparty_node_id, msg), *counterparty_node_id);
        }
 
        fn handle_update_fee(&self, counterparty_node_id: &PublicKey, msg: &msgs::UpdateFee) {
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
                let _ = handle_error!(self, self.internal_update_fee(counterparty_node_id, msg), *counterparty_node_id);
        }
 
        fn handle_announcement_signatures(&self, counterparty_node_id: &PublicKey, msg: &msgs::AnnouncementSignatures) {
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
                let _ = handle_error!(self, self.internal_announcement_signatures(counterparty_node_id, msg), *counterparty_node_id);
        }
 
        fn handle_channel_update(&self, counterparty_node_id: &PublicKey, msg: &msgs::ChannelUpdate) {
                PersistenceNotifierGuard::optionally_notify(&self.total_consistency_lock, &self.persistence_notifier, || {
+                       let force_persist = self.process_background_events();
                        if let Ok(persist) = handle_error!(self, self.internal_channel_update(counterparty_node_id, msg), *counterparty_node_id) {
-                               persist
+                               if force_persist == NotifyOption::DoPersist { NotifyOption::DoPersist } else { persist }
                        } else {
                                NotifyOption::SkipPersist
                        }
@@ -6322,12 +6957,12 @@ where
        }
 
        fn handle_channel_reestablish(&self, counterparty_node_id: &PublicKey, msg: &msgs::ChannelReestablish) {
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
                let _ = handle_error!(self, self.internal_channel_reestablish(counterparty_node_id, msg), *counterparty_node_id);
        }
 
        fn peer_disconnected(&self, counterparty_node_id: &PublicKey) {
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
                let mut failed_channels = Vec::new();
                let mut per_peer_state = self.per_peer_state.write().unwrap();
                let remove_peer = {
@@ -6340,31 +6975,58 @@ where
                                peer_state.channel_by_id.retain(|_, chan| {
                                        chan.remove_uncommitted_htlcs_and_mark_paused(&self.logger);
                                        if chan.is_shutdown() {
-                                               update_maps_on_chan_removal!(self, chan);
-                                               self.issue_channel_close_events(chan, ClosureReason::DisconnectedPeer);
+                                               update_maps_on_chan_removal!(self, &chan.context);
+                                               self.issue_channel_close_events(&chan.context, ClosureReason::DisconnectedPeer);
                                                return false;
                                        }
                                        true
                                });
+                               peer_state.inbound_v1_channel_by_id.retain(|_, chan| {
+                                       update_maps_on_chan_removal!(self, &chan.context);
+                                       self.issue_channel_close_events(&chan.context, ClosureReason::DisconnectedPeer);
+                                       false
+                               });
+                               peer_state.outbound_v1_channel_by_id.retain(|_, chan| {
+                                       update_maps_on_chan_removal!(self, &chan.context);
+                                       self.issue_channel_close_events(&chan.context, ClosureReason::DisconnectedPeer);
+                                       false
+                               });
                                pending_msg_events.retain(|msg| {
                                        match msg {
+                                               // V1 Channel Establishment
                                                &events::MessageSendEvent::SendAcceptChannel { .. } => false,
                                                &events::MessageSendEvent::SendOpenChannel { .. } => false,
                                                &events::MessageSendEvent::SendFundingCreated { .. } => false,
                                                &events::MessageSendEvent::SendFundingSigned { .. } => false,
+                                               // V2 Channel Establishment
+                                               &events::MessageSendEvent::SendAcceptChannelV2 { .. } => false,
+                                               &events::MessageSendEvent::SendOpenChannelV2 { .. } => false,
+                                               // Common Channel Establishment
                                                &events::MessageSendEvent::SendChannelReady { .. } => false,
                                                &events::MessageSendEvent::SendAnnouncementSignatures { .. } => false,
+                                               // Interactive Transaction Construction
+                                               &events::MessageSendEvent::SendTxAddInput { .. } => false,
+                                               &events::MessageSendEvent::SendTxAddOutput { .. } => false,
+                                               &events::MessageSendEvent::SendTxRemoveInput { .. } => false,
+                                               &events::MessageSendEvent::SendTxRemoveOutput { .. } => false,
+                                               &events::MessageSendEvent::SendTxComplete { .. } => false,
+                                               &events::MessageSendEvent::SendTxSignatures { .. } => false,
+                                               &events::MessageSendEvent::SendTxInitRbf { .. } => false,
+                                               &events::MessageSendEvent::SendTxAckRbf { .. } => false,
+                                               &events::MessageSendEvent::SendTxAbort { .. } => false,
+                                               // Channel Operations
                                                &events::MessageSendEvent::UpdateHTLCs { .. } => false,
                                                &events::MessageSendEvent::SendRevokeAndACK { .. } => false,
                                                &events::MessageSendEvent::SendClosingSigned { .. } => false,
                                                &events::MessageSendEvent::SendShutdown { .. } => false,
                                                &events::MessageSendEvent::SendChannelReestablish { .. } => false,
+                                               &events::MessageSendEvent::HandleError { .. } => false,
+                                               // Gossip
                                                &events::MessageSendEvent::SendChannelAnnouncement { .. } => false,
                                                &events::MessageSendEvent::BroadcastChannelAnnouncement { .. } => true,
                                                &events::MessageSendEvent::BroadcastChannelUpdate { .. } => true,
                                                &events::MessageSendEvent::BroadcastNodeAnnouncement { .. } => true,
                                                &events::MessageSendEvent::SendChannelUpdate { .. } => false,
-                                               &events::MessageSendEvent::HandleError { .. } => false,
                                                &events::MessageSendEvent::SendChannelRangeQuery { .. } => false,
                                                &events::MessageSendEvent::SendShortIdsQuery { .. } => false,
                                                &events::MessageSendEvent::SendReplyChannelRange { .. } => false,
@@ -6392,7 +7054,7 @@ where
                        return Err(());
                }
 
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
 
                // If we have too many peers connected which don't have funded channels, disconnect the
                // peer immediately (as long as it doesn't have funded channels). If we have a bunch of
@@ -6410,9 +7072,12 @@ where
                                        }
                                        e.insert(Mutex::new(PeerState {
                                                channel_by_id: HashMap::new(),
+                                               outbound_v1_channel_by_id: HashMap::new(),
+                                               inbound_v1_channel_by_id: HashMap::new(),
                                                latest_features: init_msg.features.clone(),
                                                pending_msg_events: Vec::new(),
                                                monitor_update_blocked_actions: BTreeMap::new(),
+                                               actions_blocking_raa_monitor_updates: BTreeMap::new(),
                                                is_connected: true,
                                        }));
                                },
@@ -6442,8 +7107,8 @@ where
                        let peer_state = &mut *peer_state_lock;
                        let pending_msg_events = &mut peer_state.pending_msg_events;
                        peer_state.channel_by_id.retain(|_, chan| {
-                               let retain = if chan.get_counterparty_node_id() == *counterparty_node_id {
-                                       if !chan.have_received_message() {
+                               let retain = if chan.context.get_counterparty_node_id() == *counterparty_node_id {
+                                       if !chan.context.have_received_message() {
                                                // If we created this (outbound) channel while we were disconnected from the
                                                // peer we probably failed to send the open_channel message, which is now
                                                // lost. We can't have had anything pending related to this channel, so we just
@@ -6451,13 +7116,13 @@ where
                                                false
                                        } else {
                                                pending_msg_events.push(events::MessageSendEvent::SendChannelReestablish {
-                                                       node_id: chan.get_counterparty_node_id(),
+                                                       node_id: chan.context.get_counterparty_node_id(),
                                                        msg: chan.get_channel_reestablish(&self.logger),
                                                });
                                                true
                                        }
                                } else { true };
-                               if retain && chan.get_counterparty_node_id() != *counterparty_node_id {
+                               if retain && chan.context.get_counterparty_node_id() != *counterparty_node_id {
                                        if let Some(msg) = chan.get_signed_channel_announcement(&self.node_signer, self.genesis_hash.clone(), self.best_block.read().unwrap().height(), &self.default_configuration) {
                                                if let Ok(update_msg) = self.get_channel_update_for_broadcast(chan) {
                                                        pending_msg_events.push(events::MessageSendEvent::SendChannelAnnouncement {
@@ -6475,7 +7140,7 @@ where
        }
 
        fn handle_error(&self, counterparty_node_id: &PublicKey, msg: &msgs::ErrorMessage) {
-               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier);
+               let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(self);
 
                if msg.channel_id == [0; 32] {
                        let channel_ids: Vec<[u8; 32]> = {
@@ -6484,7 +7149,9 @@ where
                                if peer_state_mutex_opt.is_none() { return; }
                                let mut peer_state_lock = peer_state_mutex_opt.unwrap().lock().unwrap();
                                let peer_state = &mut *peer_state_lock;
-                               peer_state.channel_by_id.keys().cloned().collect()
+                               peer_state.channel_by_id.keys().cloned()
+                                       .chain(peer_state.outbound_v1_channel_by_id.keys().cloned())
+                                       .chain(peer_state.inbound_v1_channel_by_id.keys().cloned()).collect()
                        };
                        for channel_id in channel_ids {
                                // Untrusted messages from peer, we throw away the error if id points to a non-existent channel
@@ -6498,7 +7165,7 @@ where
                                if peer_state_mutex_opt.is_none() { return; }
                                let mut peer_state_lock = peer_state_mutex_opt.unwrap().lock().unwrap();
                                let peer_state = &mut *peer_state_lock;
-                               if let Some(chan) = peer_state.channel_by_id.get_mut(&msg.channel_id) {
+                               if let Some(chan) = peer_state.outbound_v1_channel_by_id.get_mut(&msg.channel_id) {
                                        if let Ok(msg) = chan.maybe_handle_error_without_close(self.genesis_hash) {
                                                peer_state.pending_msg_events.push(events::MessageSendEvent::SendOpenChannel {
                                                        node_id: *counterparty_node_id,
@@ -6521,6 +7188,64 @@ where
        fn provided_init_features(&self, _their_init_features: &PublicKey) -> InitFeatures {
                provided_init_features(&self.default_configuration)
        }
+
+       fn get_genesis_hashes(&self) -> Option<Vec<ChainHash>> {
+               Some(vec![ChainHash::from(&self.genesis_hash[..])])
+       }
+
+       fn handle_tx_add_input(&self, counterparty_node_id: &PublicKey, msg: &msgs::TxAddInput) {
+               let _: Result<(), _> = handle_error!(self, Err(MsgHandleErrInternal::send_err_msg_no_close(
+                       "Dual-funded channels not supported".to_owned(),
+                        msg.channel_id.clone())), *counterparty_node_id);
+       }
+
+       fn handle_tx_add_output(&self, counterparty_node_id: &PublicKey, msg: &msgs::TxAddOutput) {
+               let _: Result<(), _> = handle_error!(self, Err(MsgHandleErrInternal::send_err_msg_no_close(
+                       "Dual-funded channels not supported".to_owned(),
+                        msg.channel_id.clone())), *counterparty_node_id);
+       }
+
+       fn handle_tx_remove_input(&self, counterparty_node_id: &PublicKey, msg: &msgs::TxRemoveInput) {
+               let _: Result<(), _> = handle_error!(self, Err(MsgHandleErrInternal::send_err_msg_no_close(
+                       "Dual-funded channels not supported".to_owned(),
+                        msg.channel_id.clone())), *counterparty_node_id);
+       }
+
+       fn handle_tx_remove_output(&self, counterparty_node_id: &PublicKey, msg: &msgs::TxRemoveOutput) {
+               let _: Result<(), _> = handle_error!(self, Err(MsgHandleErrInternal::send_err_msg_no_close(
+                       "Dual-funded channels not supported".to_owned(),
+                        msg.channel_id.clone())), *counterparty_node_id);
+       }
+
+       fn handle_tx_complete(&self, counterparty_node_id: &PublicKey, msg: &msgs::TxComplete) {
+               let _: Result<(), _> = handle_error!(self, Err(MsgHandleErrInternal::send_err_msg_no_close(
+                       "Dual-funded channels not supported".to_owned(),
+                        msg.channel_id.clone())), *counterparty_node_id);
+       }
+
+       fn handle_tx_signatures(&self, counterparty_node_id: &PublicKey, msg: &msgs::TxSignatures) {
+               let _: Result<(), _> = handle_error!(self, Err(MsgHandleErrInternal::send_err_msg_no_close(
+                       "Dual-funded channels not supported".to_owned(),
+                        msg.channel_id.clone())), *counterparty_node_id);
+       }
+
+       fn handle_tx_init_rbf(&self, counterparty_node_id: &PublicKey, msg: &msgs::TxInitRbf) {
+               let _: Result<(), _> = handle_error!(self, Err(MsgHandleErrInternal::send_err_msg_no_close(
+                       "Dual-funded channels not supported".to_owned(),
+                        msg.channel_id.clone())), *counterparty_node_id);
+       }
+
+       fn handle_tx_ack_rbf(&self, counterparty_node_id: &PublicKey, msg: &msgs::TxAckRbf) {
+               let _: Result<(), _> = handle_error!(self, Err(MsgHandleErrInternal::send_err_msg_no_close(
+                       "Dual-funded channels not supported".to_owned(),
+                        msg.channel_id.clone())), *counterparty_node_id);
+       }
+
+       fn handle_tx_abort(&self, counterparty_node_id: &PublicKey, msg: &msgs::TxAbort) {
+               let _: Result<(), _> = handle_error!(self, Err(MsgHandleErrInternal::send_err_msg_no_close(
+                       "Dual-funded channels not supported".to_owned(),
+                        msg.channel_id.clone())), *counterparty_node_id);
+       }
 }
 
 /// Fetches the set of [`NodeFeatures`] flags which are provided by or required by
@@ -6558,7 +7283,7 @@ pub fn provided_init_features(_config: &UserConfig) -> InitFeatures {
        // should also add the corresponding (optional) bit to the [`ChannelMessageHandler`] impl for
        // [`ErroringMessageHandler`].
        let mut features = InitFeatures::empty();
-       features.set_data_loss_protect_optional();
+       features.set_data_loss_protect_required();
        features.set_upfront_shutdown_script_optional();
        features.set_variable_length_onion_required();
        features.set_static_remote_key_required();
@@ -6617,10 +7342,9 @@ impl Writeable for ChannelDetails {
                        (14, user_channel_id_low, required),
                        (16, self.balance_msat, required),
                        (18, self.outbound_capacity_msat, required),
-                       // Note that by the time we get past the required read above, outbound_capacity_msat will be
-                       // filled in, so we can safely unwrap it here.
-                       (19, self.next_outbound_htlc_limit_msat, (default_value, outbound_capacity_msat.0.unwrap() as u64)),
+                       (19, self.next_outbound_htlc_limit_msat, required),
                        (20, self.inbound_capacity_msat, required),
+                       (21, self.next_outbound_htlc_minimum_msat, required),
                        (22, self.confirmations_required, option),
                        (24, self.force_close_spend_delay, option),
                        (26, self.is_outbound, required),
@@ -6657,6 +7381,7 @@ impl Readable for ChannelDetails {
                        // filled in, so we can safely unwrap it here.
                        (19, next_outbound_htlc_limit_msat, (default_value, outbound_capacity_msat.0.unwrap() as u64)),
                        (20, inbound_capacity_msat, required),
+                       (21, next_outbound_htlc_minimum_msat, (default_value, 0)),
                        (22, confirmations_required, option),
                        (24, force_close_spend_delay, option),
                        (26, is_outbound, required),
@@ -6690,6 +7415,7 @@ impl Readable for ChannelDetails {
                        balance_msat: balance_msat.0.unwrap(),
                        outbound_capacity_msat: outbound_capacity_msat.0.unwrap(),
                        next_outbound_htlc_limit_msat: next_outbound_htlc_limit_msat.0.unwrap(),
+                       next_outbound_htlc_minimum_msat: next_outbound_htlc_minimum_msat.0.unwrap(),
                        inbound_capacity_msat: inbound_capacity_msat.0.unwrap(),
                        confirmations_required,
                        confirmations,
@@ -6720,10 +7446,13 @@ impl_writeable_tlv_based_enum!(PendingHTLCRouting,
                (0, payment_data, required),
                (1, phantom_shared_secret, option),
                (2, incoming_cltv_expiry, required),
+               (3, payment_metadata, option),
        },
        (2, ReceiveKeysend) => {
                (0, payment_preimage, required),
                (2, incoming_cltv_expiry, required),
+               (3, payment_metadata, option),
+               (4, payment_data, option), // Added in 0.0.116
        },
 ;);
 
@@ -6734,6 +7463,7 @@ impl_writeable_tlv_based!(PendingHTLCInfo, {
        (6, outgoing_amt_msat, required),
        (8, outgoing_cltv_value, required),
        (9, incoming_amt_msat, option),
+       (10, skimmed_fee_msat, option),
 });
 
 
@@ -6832,6 +7562,7 @@ impl Writeable for ClaimableHTLC {
                        (5, self.total_value_received, option),
                        (6, self.cltv_expiry, required),
                        (8, keysend_preimage, option),
+                       (10, self.counterparty_skimmed_fee_msat, option),
                });
                Ok(())
        }
@@ -6839,24 +7570,19 @@ impl Writeable for ClaimableHTLC {
 
 impl Readable for ClaimableHTLC {
        fn read<R: Read>(reader: &mut R) -> Result<Self, DecodeError> {
-               let mut prev_hop = crate::util::ser::RequiredWrapper(None);
-               let mut value = 0;
-               let mut sender_intended_value = None;
-               let mut payment_data: Option<msgs::FinalOnionHopData> = None;
-               let mut cltv_expiry = 0;
-               let mut total_value_received = None;
-               let mut total_msat = None;
-               let mut keysend_preimage: Option<PaymentPreimage> = None;
-               read_tlv_fields!(reader, {
+               _init_and_read_tlv_fields!(reader, {
                        (0, prev_hop, required),
                        (1, total_msat, option),
-                       (2, value, required),
+                       (2, value_ser, required),
                        (3, sender_intended_value, option),
-                       (4, payment_data, option),
+                       (4, payment_data_opt, option),
                        (5, total_value_received, option),
                        (6, cltv_expiry, required),
-                       (8, keysend_preimage, option)
+                       (8, keysend_preimage, option),
+                       (10, counterparty_skimmed_fee_msat, option),
                });
+               let payment_data: Option<msgs::FinalOnionHopData> = payment_data_opt;
+               let value = value_ser.0.unwrap();
                let onion_payload = match keysend_preimage {
                        Some(p) => {
                                if payment_data.is_some() {
@@ -6885,7 +7611,8 @@ impl Readable for ClaimableHTLC {
                        total_value_received,
                        total_msat: total_msat.unwrap(),
                        onion_payload,
-                       cltv_expiry,
+                       cltv_expiry: cltv_expiry.0.unwrap(),
+                       counterparty_skimmed_fee_msat,
                })
        }
 }
@@ -6897,30 +7624,32 @@ impl Readable for HTLCSource {
                        0 => {
                                let mut session_priv: crate::util::ser::RequiredWrapper<SecretKey> = crate::util::ser::RequiredWrapper(None);
                                let mut first_hop_htlc_msat: u64 = 0;
-                               let mut path: Option<Vec<RouteHop>> = Some(Vec::new());
+                               let mut path_hops: Option<Vec<RouteHop>> = Some(Vec::new());
                                let mut payment_id = None;
-                               let mut payment_secret = None;
                                let mut payment_params: Option<PaymentParameters> = None;
+                               let mut blinded_tail: Option<BlindedTail> = None;
                                read_tlv_fields!(reader, {
                                        (0, session_priv, required),
                                        (1, payment_id, option),
                                        (2, first_hop_htlc_msat, required),
-                                       (3, payment_secret, option),
-                                       (4, path, vec_type),
+                                       (4, path_hops, vec_type),
                                        (5, payment_params, (option: ReadableArgs, 0)),
+                                       (6, blinded_tail, option),
                                });
                                if payment_id.is_none() {
                                        // For backwards compat, if there was no payment_id written, use the session_priv bytes
                                        // instead.
                                        payment_id = Some(PaymentId(*session_priv.0.unwrap().as_ref()));
                                }
-                               if path.is_none() || path.as_ref().unwrap().is_empty() {
+                               let path = Path { hops: path_hops.ok_or(DecodeError::InvalidValue)?, blinded_tail };
+                               if path.hops.len() == 0 {
                                        return Err(DecodeError::InvalidValue);
                                }
-                               let path = path.unwrap();
                                if let Some(params) = payment_params.as_mut() {
-                                       if params.final_cltv_expiry_delta == 0 {
-                                               params.final_cltv_expiry_delta = path.last().unwrap().cltv_expiry_delta;
+                                       if let Payee::Clear { ref mut final_cltv_expiry_delta, .. } = params.payee {
+                                               if final_cltv_expiry_delta == &0 {
+                                                       *final_cltv_expiry_delta = path.final_cltv_expiry_delta().ok_or(DecodeError::InvalidValue)?;
+                                               }
                                        }
                                }
                                Ok(HTLCSource::OutboundRoute {
@@ -6928,7 +7657,6 @@ impl Readable for HTLCSource {
                                        first_hop_htlc_msat,
                                        path,
                                        payment_id: payment_id.unwrap(),
-                                       payment_secret,
                                })
                        }
                        1 => Ok(HTLCSource::PreviousHopData(Readable::read(reader)?)),
@@ -6940,16 +7668,17 @@ impl Readable for HTLCSource {
 impl Writeable for HTLCSource {
        fn write<W: Writer>(&self, writer: &mut W) -> Result<(), crate::io::Error> {
                match self {
-                       HTLCSource::OutboundRoute { ref session_priv, ref first_hop_htlc_msat, ref path, payment_id, payment_secret } => {
+                       HTLCSource::OutboundRoute { ref session_priv, ref first_hop_htlc_msat, ref path, payment_id } => {
                                0u8.write(writer)?;
                                let payment_id_opt = Some(payment_id);
                                write_tlv_fields!(writer, {
                                        (0, session_priv, required),
                                        (1, payment_id_opt, option),
                                        (2, first_hop_htlc_msat, required),
-                                       (3, payment_secret, option),
-                                       (4, *path, vec_type),
+                                       // 3 was previously used to write a PaymentSecret for the payment.
+                                       (4, path.hops, vec_type),
                                        (5, None::<PaymentParameters>, option), // payment_params in LDK versions prior to 0.0.115
+                                       (6, path.blinded_tail, option),
                                 });
                        }
                        HTLCSource::PreviousHopData(ref field) => {
@@ -7021,7 +7750,7 @@ where
                                }
                                number_of_channels += peer_state.channel_by_id.len();
                                for (_, channel) in peer_state.channel_by_id.iter() {
-                                       if !channel.is_funding_initiated() {
+                                       if !channel.context.is_funding_initiated() {
                                                unfunded_channels += 1;
                                        }
                                }
@@ -7033,7 +7762,7 @@ where
                                let mut peer_state_lock = peer_state_mutex.lock().unwrap();
                                let peer_state = &mut *peer_state_lock;
                                for (_, channel) in peer_state.channel_by_id.iter() {
-                                       if channel.is_funding_initiated() {
+                                       if channel.context.is_funding_initiated() {
                                                channel.write(writer)?;
                                        }
                                }
@@ -7059,14 +7788,16 @@ where
                let pending_outbound_payments = self.pending_outbound_payments.pending_outbound_payments.lock().unwrap();
 
                let mut htlc_purposes: Vec<&events::PaymentPurpose> = Vec::new();
-               (claimable_payments.claimable_htlcs.len() as u64).write(writer)?;
-               for (payment_hash, (purpose, previous_hops)) in claimable_payments.claimable_htlcs.iter() {
+               let mut htlc_onion_fields: Vec<&_> = Vec::new();
+               (claimable_payments.claimable_payments.len() as u64).write(writer)?;
+               for (payment_hash, payment) in claimable_payments.claimable_payments.iter() {
                        payment_hash.write(writer)?;
-                       (previous_hops.len() as u64).write(writer)?;
-                       for htlc in previous_hops.iter() {
+                       (payment.htlcs.len() as u64).write(writer)?;
+                       for htlc in payment.htlcs.iter() {
                                htlc.write(writer)?;
                        }
-                       htlc_purposes.push(purpose);
+                       htlc_purposes.push(&payment.purpose);
+                       htlc_onion_fields.push(&payment.onion_fields);
                }
 
                let mut monitor_update_blocked_actions_per_peer = None;
@@ -7096,23 +7827,28 @@ where
                }
 
                let events = self.pending_events.lock().unwrap();
-               (events.len() as u64).write(writer)?;
-               for event in events.iter() {
-                       event.write(writer)?;
-               }
-
-               let background_events = self.pending_background_events.lock().unwrap();
-               (background_events.len() as u64).write(writer)?;
-               for event in background_events.iter() {
-                       match event {
-                               BackgroundEvent::ClosingMonitorUpdate((funding_txo, monitor_update)) => {
-                                       0u8.write(writer)?;
-                                       funding_txo.write(writer)?;
-                                       monitor_update.write(writer)?;
-                               },
+               // LDK versions prior to 0.0.115 don't support post-event actions, thus if there's no
+               // actions at all, skip writing the required TLV. Otherwise, pre-0.0.115 versions will
+               // refuse to read the new ChannelManager.
+               let events_not_backwards_compatible = events.iter().any(|(_, action)| action.is_some());
+               if events_not_backwards_compatible {
+                       // If we're gonna write a even TLV that will overwrite our events anyway we might as
+                       // well save the space and not write any events here.
+                       0u64.write(writer)?;
+               } else {
+                       (events.len() as u64).write(writer)?;
+                       for (event, _) in events.iter() {
+                               event.write(writer)?;
                        }
                }
 
+               // LDK versions prior to 0.0.116 wrote the `pending_background_events`
+               // `MonitorUpdateRegeneratedOnStartup`s here, however there was never a reason to do so -
+               // the closing monitor updates were always effectively replayed on startup (either directly
+               // by calling `broadcast_latest_holder_commitment_txn` on a `ChannelMonitor` during
+               // deserialization or, in 0.0.115, by regenerating the monitor update itself).
+               0u64.write(writer)?;
+
                // Prior to 0.0.111 we tracked node_announcement serials here, however that now happens in
                // `PeerManager`, and thus we simply write the `highest_seen_timestamp` twice, which is
                // likely to be identical.
@@ -7179,14 +7915,57 @@ where
                        (5, self.our_network_pubkey, required),
                        (6, monitor_update_blocked_actions_per_peer, option),
                        (7, self.fake_scid_rand_bytes, required),
+                       (8, if events_not_backwards_compatible { Some(&*events) } else { None }, option),
                        (9, htlc_purposes, vec_type),
                        (11, self.probing_cookie_secret, required),
+                       (13, htlc_onion_fields, optional_vec),
                });
 
                Ok(())
        }
 }
 
+impl Writeable for VecDeque<(Event, Option<EventCompletionAction>)> {
+       fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
+               (self.len() as u64).write(w)?;
+               for (event, action) in self.iter() {
+                       event.write(w)?;
+                       action.write(w)?;
+                       #[cfg(debug_assertions)] {
+                               // Events are MaybeReadable, in some cases indicating that they shouldn't actually
+                               // be persisted and are regenerated on restart. However, if such an event has a
+                               // post-event-handling action we'll write nothing for the event and would have to
+                               // either forget the action or fail on deserialization (which we do below). Thus,
+                               // check that the event is sane here.
+                               let event_encoded = event.encode();
+                               let event_read: Option<Event> =
+                                       MaybeReadable::read(&mut &event_encoded[..]).unwrap();
+                               if action.is_some() { assert!(event_read.is_some()); }
+                       }
+               }
+               Ok(())
+       }
+}
+impl Readable for VecDeque<(Event, Option<EventCompletionAction>)> {
+       fn read<R: Read>(reader: &mut R) -> Result<Self, DecodeError> {
+               let len: u64 = Readable::read(reader)?;
+               const MAX_ALLOC_SIZE: u64 = 1024 * 16;
+               let mut events: Self = VecDeque::with_capacity(cmp::min(
+                       MAX_ALLOC_SIZE/mem::size_of::<(events::Event, Option<EventCompletionAction>)>() as u64,
+                       len) as usize);
+               for _ in 0..len {
+                       let ev_opt = MaybeReadable::read(reader)?;
+                       let action = Readable::read(reader)?;
+                       if let Some(ev) = ev_opt {
+                               events.push_back((ev, action));
+                       } else if action.is_some() {
+                               return Err(DecodeError::InvalidValue);
+                       }
+               }
+               Ok(events)
+       }
+}
+
 /// Arguments for the creation of a ChannelManager that are not deserialized.
 ///
 /// At a high-level, the process for deserializing a ChannelManager and resuming normal operation
@@ -7269,7 +8048,7 @@ where
        pub default_config: UserConfig,
 
        /// A map from channel funding outpoints to ChannelMonitors for those channels (ie
-       /// value.get_funding_txo() should be the key).
+       /// value.context.get_funding_txo() should be the key).
        ///
        /// If a monitor is inconsistent with the channel state during deserialization the channel will
        /// be force-closed using the data in the ChannelMonitor and the channel will be dropped. This
@@ -7353,23 +8132,20 @@ where
                let mut peer_channels: HashMap<PublicKey, HashMap<[u8; 32], Channel<<SP::Target as SignerProvider>::Signer>>> = HashMap::with_capacity(cmp::min(channel_count as usize, 128));
                let mut id_to_peer = HashMap::with_capacity(cmp::min(channel_count as usize, 128));
                let mut short_to_chan_info = HashMap::with_capacity(cmp::min(channel_count as usize, 128));
-               let mut channel_closures = Vec::new();
+               let mut channel_closures = VecDeque::new();
                let mut pending_background_events = Vec::new();
                for _ in 0..channel_count {
                        let mut channel: Channel<<SP::Target as SignerProvider>::Signer> = Channel::read(reader, (
                                &args.entropy_source, &args.signer_provider, best_block_height, &provided_channel_type_features(&args.default_config)
                        ))?;
-                       let funding_txo = channel.get_funding_txo().ok_or(DecodeError::InvalidValue)?;
+                       let funding_txo = channel.context.get_funding_txo().ok_or(DecodeError::InvalidValue)?;
                        funding_txo_set.insert(funding_txo.clone());
                        if let Some(ref mut monitor) = args.channel_monitors.get_mut(&funding_txo) {
-                               if channel.get_cur_holder_commitment_transaction_number() < monitor.get_cur_holder_commitment_number() ||
-                                               channel.get_revoked_counterparty_commitment_transaction_number() < monitor.get_min_seen_secret() ||
-                                               channel.get_cur_counterparty_commitment_transaction_number() < monitor.get_cur_counterparty_commitment_number() ||
-                                               channel.get_latest_monitor_update_id() > monitor.get_latest_update_id() {
+                               if channel.get_latest_complete_monitor_update_id() > monitor.get_latest_update_id() {
                                        // If the channel is ahead of the monitor, return InvalidValue:
                                        log_error!(args.logger, "A ChannelMonitor is stale compared to the current ChannelManager! This indicates a potentially-critical violation of the chain::Watch API!");
                                        log_error!(args.logger, " The ChannelMonitor for channel {} is at update_id {} but the ChannelManager is at update_id {}.",
-                                               log_bytes!(channel.channel_id()), monitor.get_latest_update_id(), channel.get_latest_monitor_update_id());
+                                               log_bytes!(channel.context.channel_id()), monitor.get_latest_update_id(), channel.get_latest_complete_monitor_update_id());
                                        log_error!(args.logger, " The chain::Watch API *requires* that monitors are persisted durably before returning,");
                                        log_error!(args.logger, " client applications must ensure that ChannelMonitor data is always available and the latest to avoid funds loss!");
                                        log_error!(args.logger, " Without the latest ChannelMonitor we cannot continue without risking funds.");
@@ -7378,22 +8154,24 @@ where
                                } else if channel.get_cur_holder_commitment_transaction_number() > monitor.get_cur_holder_commitment_number() ||
                                                channel.get_revoked_counterparty_commitment_transaction_number() > monitor.get_min_seen_secret() ||
                                                channel.get_cur_counterparty_commitment_transaction_number() > monitor.get_cur_counterparty_commitment_number() ||
-                                               channel.get_latest_monitor_update_id() < monitor.get_latest_update_id() {
+                                               channel.context.get_latest_monitor_update_id() < monitor.get_latest_update_id() {
                                        // But if the channel is behind of the monitor, close the channel:
                                        log_error!(args.logger, "A ChannelManager is stale compared to the current ChannelMonitor!");
                                        log_error!(args.logger, " The channel will be force-closed and the latest commitment transaction from the ChannelMonitor broadcast.");
                                        log_error!(args.logger, " The ChannelMonitor for channel {} is at update_id {} but the ChannelManager is at update_id {}.",
-                                               log_bytes!(channel.channel_id()), monitor.get_latest_update_id(), channel.get_latest_monitor_update_id());
-                                       let (monitor_update, mut new_failed_htlcs) = channel.force_shutdown(true);
-                                       if let Some(monitor_update) = monitor_update {
-                                               pending_background_events.push(BackgroundEvent::ClosingMonitorUpdate(monitor_update));
+                                               log_bytes!(channel.context.channel_id()), monitor.get_latest_update_id(), channel.context.get_latest_monitor_update_id());
+                                       let (monitor_update, mut new_failed_htlcs) = channel.context.force_shutdown(true);
+                                       if let Some((counterparty_node_id, funding_txo, update)) = monitor_update {
+                                               pending_background_events.push(BackgroundEvent::MonitorUpdateRegeneratedOnStartup {
+                                                       counterparty_node_id, funding_txo, update
+                                               });
                                        }
                                        failed_htlcs.append(&mut new_failed_htlcs);
-                                       channel_closures.push(events::Event::ChannelClosed {
-                                               channel_id: channel.channel_id(),
-                                               user_channel_id: channel.get_user_id(),
+                                       channel_closures.push_back((events::Event::ChannelClosed {
+                                               channel_id: channel.context.channel_id(),
+                                               user_channel_id: channel.context.get_user_id(),
                                                reason: ClosureReason::OutdatedChannelManager
-                                       });
+                                       }, None));
                                        for (channel_htlc_source, payment_hash) in channel.inflight_htlc_sources() {
                                                let mut found_htlc = false;
                                                for (monitor_htlc_source, _) in monitor.get_all_current_outbound_htlcs() {
@@ -7409,26 +8187,29 @@ where
                                                        // backwards leg of the HTLC will simply be rejected.
                                                        log_info!(args.logger,
                                                                "Failing HTLC with hash {} as it is missing in the ChannelMonitor for channel {} but was present in the (stale) ChannelManager",
-                                                               log_bytes!(channel.channel_id()), log_bytes!(payment_hash.0));
-                                                       failed_htlcs.push((channel_htlc_source.clone(), *payment_hash, channel.get_counterparty_node_id(), channel.channel_id()));
+                                                               log_bytes!(channel.context.channel_id()), log_bytes!(payment_hash.0));
+                                                       failed_htlcs.push((channel_htlc_source.clone(), *payment_hash, channel.context.get_counterparty_node_id(), channel.context.channel_id()));
                                                }
                                        }
                                } else {
-                                       log_info!(args.logger, "Successfully loaded channel {}", log_bytes!(channel.channel_id()));
-                                       if let Some(short_channel_id) = channel.get_short_channel_id() {
-                                               short_to_chan_info.insert(short_channel_id, (channel.get_counterparty_node_id(), channel.channel_id()));
+                                       log_info!(args.logger, "Successfully loaded channel {} at update_id {} against monitor at update id {}",
+                                               log_bytes!(channel.context.channel_id()), channel.context.get_latest_monitor_update_id(),
+                                               monitor.get_latest_update_id());
+                                       channel.complete_all_mon_updates_through(monitor.get_latest_update_id());
+                                       if let Some(short_channel_id) = channel.context.get_short_channel_id() {
+                                               short_to_chan_info.insert(short_channel_id, (channel.context.get_counterparty_node_id(), channel.context.channel_id()));
                                        }
-                                       if channel.is_funding_initiated() {
-                                               id_to_peer.insert(channel.channel_id(), channel.get_counterparty_node_id());
+                                       if channel.context.is_funding_initiated() {
+                                               id_to_peer.insert(channel.context.channel_id(), channel.context.get_counterparty_node_id());
                                        }
-                                       match peer_channels.entry(channel.get_counterparty_node_id()) {
+                                       match peer_channels.entry(channel.context.get_counterparty_node_id()) {
                                                hash_map::Entry::Occupied(mut entry) => {
                                                        let by_id_map = entry.get_mut();
-                                                       by_id_map.insert(channel.channel_id(), channel);
+                                                       by_id_map.insert(channel.context.channel_id(), channel);
                                                },
                                                hash_map::Entry::Vacant(entry) => {
                                                        let mut by_id_map = HashMap::new();
-                                                       by_id_map.insert(channel.channel_id(), channel);
+                                                       by_id_map.insert(channel.context.channel_id(), channel);
                                                        entry.insert(by_id_map);
                                                }
                                        }
@@ -7437,14 +8218,14 @@ where
                                // If we were persisted and shut down while the initial ChannelMonitor persistence
                                // was in-progress, we never broadcasted the funding transaction and can still
                                // safely discard the channel.
-                               let _ = channel.force_shutdown(false);
-                               channel_closures.push(events::Event::ChannelClosed {
-                                       channel_id: channel.channel_id(),
-                                       user_channel_id: channel.get_user_id(),
+                               let _ = channel.context.force_shutdown(false);
+                               channel_closures.push_back((events::Event::ChannelClosed {
+                                       channel_id: channel.context.channel_id(),
+                                       user_channel_id: channel.context.get_user_id(),
                                        reason: ClosureReason::DisconnectedPeer,
-                               });
+                               }, None));
                        } else {
-                               log_error!(args.logger, "Missing ChannelMonitor for channel {} needed by ChannelManager.", log_bytes!(channel.channel_id()));
+                               log_error!(args.logger, "Missing ChannelMonitor for channel {} needed by ChannelManager.", log_bytes!(channel.context.channel_id()));
                                log_error!(args.logger, " The chain::Watch API *requires* that monitors are persisted durably before returning,");
                                log_error!(args.logger, " client applications must ensure that ChannelMonitor data is always available and the latest to avoid funds loss!");
                                log_error!(args.logger, " Without the ChannelMonitor we cannot continue without risking funds.");
@@ -7455,11 +8236,13 @@ where
 
                for (funding_txo, _) in args.channel_monitors.iter() {
                        if !funding_txo_set.contains(funding_txo) {
+                               log_info!(args.logger, "Queueing monitor update to ensure missing channel {} is force closed",
+                                       log_bytes!(funding_txo.to_channel_id()));
                                let monitor_update = ChannelMonitorUpdate {
                                        update_id: CLOSED_CHANNEL_UPDATE_ID,
                                        updates: vec![ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast: true }],
                                };
-                               pending_background_events.push(BackgroundEvent::ClosingMonitorUpdate((*funding_txo, monitor_update)));
+                               pending_background_events.push(BackgroundEvent::ClosingMonitorUpdateRegeneratedOnStartup((*funding_txo, monitor_update)));
                        }
                }
 
@@ -7494,19 +8277,23 @@ where
                        let peer_pubkey = Readable::read(reader)?;
                        let peer_state = PeerState {
                                channel_by_id: peer_channels.remove(&peer_pubkey).unwrap_or(HashMap::new()),
+                               outbound_v1_channel_by_id: HashMap::new(),
+                               inbound_v1_channel_by_id: HashMap::new(),
                                latest_features: Readable::read(reader)?,
                                pending_msg_events: Vec::new(),
                                monitor_update_blocked_actions: BTreeMap::new(),
+                               actions_blocking_raa_monitor_updates: BTreeMap::new(),
                                is_connected: false,
                        };
                        per_peer_state.insert(peer_pubkey, Mutex::new(peer_state));
                }
 
                let event_count: u64 = Readable::read(reader)?;
-               let mut pending_events_read: Vec<events::Event> = Vec::with_capacity(cmp::min(event_count as usize, MAX_ALLOC_SIZE/mem::size_of::<events::Event>()));
+               let mut pending_events_read: VecDeque<(events::Event, Option<EventCompletionAction>)> =
+                       VecDeque::with_capacity(cmp::min(event_count as usize, MAX_ALLOC_SIZE/mem::size_of::<(events::Event, Option<EventCompletionAction>)>()));
                for _ in 0..event_count {
                        match MaybeReadable::read(reader)? {
-                               Some(event) => pending_events_read.push(event),
+                               Some(event) => pending_events_read.push_back((event, None)),
                                None => continue,
                        }
                }
@@ -7515,18 +8302,34 @@ where
                for _ in 0..background_event_count {
                        match <u8 as Readable>::read(reader)? {
                                0 => {
-                                       let (funding_txo, monitor_update): (OutPoint, ChannelMonitorUpdate) = (Readable::read(reader)?, Readable::read(reader)?);
-                                       if pending_background_events.iter().find(|e| {
-                                               let BackgroundEvent::ClosingMonitorUpdate((pending_funding_txo, pending_monitor_update)) = e;
-                                               *pending_funding_txo == funding_txo && *pending_monitor_update == monitor_update
-                                       }).is_none() {
-                                               pending_background_events.push(BackgroundEvent::ClosingMonitorUpdate((funding_txo, monitor_update)));
-                                       }
+                                       // LDK versions prior to 0.0.116 wrote pending `MonitorUpdateRegeneratedOnStartup`s here,
+                                       // however we really don't (and never did) need them - we regenerate all
+                                       // on-startup monitor updates.
+                                       let _: OutPoint = Readable::read(reader)?;
+                                       let _: ChannelMonitorUpdate = Readable::read(reader)?;
                                }
                                _ => return Err(DecodeError::InvalidValue),
                        }
                }
 
+               for (node_id, peer_mtx) in per_peer_state.iter() {
+                       let peer_state = peer_mtx.lock().unwrap();
+                       for (_, chan) in peer_state.channel_by_id.iter() {
+                               for update in chan.uncompleted_unblocked_mon_updates() {
+                                       if let Some(funding_txo) = chan.context.get_funding_txo() {
+                                               log_trace!(args.logger, "Replaying ChannelMonitorUpdate {} for channel {}",
+                                                       update.update_id, log_bytes!(funding_txo.to_channel_id()));
+                                               pending_background_events.push(
+                                                       BackgroundEvent::MonitorUpdateRegeneratedOnStartup {
+                                                               counterparty_node_id: *node_id, funding_txo, update: update.clone(),
+                                                       });
+                                       } else {
+                                               return Err(DecodeError::InvalidValue);
+                                       }
+                               }
+                       }
+               }
+
                let _last_node_announcement_serial: u32 = Readable::read(reader)?; // Only used < 0.0.111
                let highest_seen_timestamp: u32 = Readable::read(reader)?;
 
@@ -7559,8 +8362,10 @@ where
                let mut fake_scid_rand_bytes: Option<[u8; 32]> = None;
                let mut probing_cookie_secret: Option<[u8; 32]> = None;
                let mut claimable_htlc_purposes = None;
+               let mut claimable_htlc_onion_fields = None;
                let mut pending_claiming_payments = Some(HashMap::new());
-               let mut monitor_update_blocked_actions_per_peer = Some(Vec::new());
+               let mut monitor_update_blocked_actions_per_peer: Option<Vec<(_, BTreeMap<_, Vec<_>>)>> = Some(Vec::new());
+               let mut events_override = None;
                read_tlv_fields!(reader, {
                        (1, pending_outbound_payments_no_retry, option),
                        (2, pending_intercepted_htlcs, option),
@@ -7569,8 +8374,10 @@ where
                        (5, received_network_pubkey, option),
                        (6, monitor_update_blocked_actions_per_peer, option),
                        (7, fake_scid_rand_bytes, option),
+                       (8, events_override, option),
                        (9, claimable_htlc_purposes, vec_type),
                        (11, probing_cookie_secret, option),
+                       (13, claimable_htlc_onion_fields, optional_vec),
                });
                if fake_scid_rand_bytes.is_none() {
                        fake_scid_rand_bytes = Some(args.entropy_source.get_secure_random_bytes());
@@ -7580,6 +8387,10 @@ where
                        probing_cookie_secret = Some(args.entropy_source.get_secure_random_bytes());
                }
 
+               if let Some(events) = events_override {
+                       pending_events_read = events;
+               }
+
                if !channel_closures.is_empty() {
                        pending_events_read.append(&mut channel_closures);
                }
@@ -7610,13 +8421,13 @@ where
                        for (_, monitor) in args.channel_monitors.iter() {
                                if id_to_peer.get(&monitor.get_funding_txo().0.to_channel_id()).is_none() {
                                        for (htlc_source, (htlc, _)) in monitor.get_pending_or_resolved_outbound_htlcs() {
-                                               if let HTLCSource::OutboundRoute { payment_id, session_priv, path, payment_secret, .. } = htlc_source {
-                                                       if path.is_empty() {
+                                               if let HTLCSource::OutboundRoute { payment_id, session_priv, path, .. } = htlc_source {
+                                                       if path.hops.is_empty() {
                                                                log_error!(args.logger, "Got an empty path for a pending payment");
                                                                return Err(DecodeError::InvalidValue);
                                                        }
 
-                                                       let path_amt = path.last().unwrap().fee_msat;
+                                                       let path_amt = path.final_value_msat();
                                                        let mut session_priv_bytes = [0; 32];
                                                        session_priv_bytes[..].copy_from_slice(&session_priv[..]);
                                                        match pending_outbounds.pending_outbound_payments.lock().unwrap().entry(payment_id) {
@@ -7626,14 +8437,15 @@ where
                                                                                if newly_added { "Added" } else { "Had" }, path_amt, log_bytes!(session_priv_bytes), log_bytes!(htlc.payment_hash.0));
                                                                },
                                                                hash_map::Entry::Vacant(entry) => {
-                                                                       let path_fee = path.get_path_fees();
+                                                                       let path_fee = path.fee_msat();
                                                                        entry.insert(PendingOutboundPayment::Retryable {
                                                                                retry_strategy: None,
                                                                                attempts: PaymentAttempts::new(),
                                                                                payment_params: None,
                                                                                session_privs: [session_priv_bytes].iter().map(|a| *a).collect(),
                                                                                payment_hash: htlc.payment_hash,
-                                                                               payment_secret,
+                                                                               payment_secret: None, // only used for retries, and we'll never retry on startup
+                                                                               payment_metadata: None, // only used for retries, and we'll never retry on startup
                                                                                keysend_preimage: None, // only used for retries, and we'll never retry on startup
                                                                                pending_amt_msat: path_amt,
                                                                                pending_fee_msat: Some(path_fee),
@@ -7674,7 +8486,7 @@ where
                                                                        if pending_forward_matches_htlc(&htlc_info) {
                                                                                log_info!(args.logger, "Removing pending intercepted HTLC with hash {} as it was forwarded to the closed channel {}",
                                                                                        log_bytes!(htlc.payment_hash.0), log_bytes!(monitor.get_funding_txo().0.to_channel_id()));
-                                                                               pending_events_read.retain(|event| {
+                                                                               pending_events_read.retain(|(event, _)| {
                                                                                        if let Event::HTLCIntercepted { intercept_id: ev_id, .. } = event {
                                                                                                intercepted_id != ev_id
                                                                                        } else { true }
@@ -7710,30 +8522,47 @@ where
                        // shut down before the timer hit. Either way, set the time_forwardable to a small
                        // constant as enough time has likely passed that we should simply handle the forwards
                        // now, or at least after the user gets a chance to reconnect to our peers.
-                       pending_events_read.push(events::Event::PendingHTLCsForwardable {
+                       pending_events_read.push_back((events::Event::PendingHTLCsForwardable {
                                time_forwardable: Duration::from_secs(2),
-                       });
+                       }, None));
                }
 
                let inbound_pmt_key_material = args.node_signer.get_inbound_payment_key_material();
                let expanded_inbound_key = inbound_payment::ExpandedKey::new(&inbound_pmt_key_material);
 
-               let mut claimable_htlcs = HashMap::with_capacity(claimable_htlcs_list.len());
-               if let Some(mut purposes) = claimable_htlc_purposes {
+               let mut claimable_payments = HashMap::with_capacity(claimable_htlcs_list.len());
+               if let Some(purposes) = claimable_htlc_purposes {
                        if purposes.len() != claimable_htlcs_list.len() {
                                return Err(DecodeError::InvalidValue);
                        }
-                       for (purpose, (payment_hash, previous_hops)) in purposes.drain(..).zip(claimable_htlcs_list.drain(..)) {
-                               claimable_htlcs.insert(payment_hash, (purpose, previous_hops));
+                       if let Some(onion_fields) = claimable_htlc_onion_fields {
+                               if onion_fields.len() != claimable_htlcs_list.len() {
+                                       return Err(DecodeError::InvalidValue);
+                               }
+                               for (purpose, (onion, (payment_hash, htlcs))) in
+                                       purposes.into_iter().zip(onion_fields.into_iter().zip(claimable_htlcs_list.into_iter()))
+                               {
+                                       let existing_payment = claimable_payments.insert(payment_hash, ClaimablePayment {
+                                               purpose, htlcs, onion_fields: onion,
+                                       });
+                                       if existing_payment.is_some() { return Err(DecodeError::InvalidValue); }
+                               }
+                       } else {
+                               for (purpose, (payment_hash, htlcs)) in purposes.into_iter().zip(claimable_htlcs_list.into_iter()) {
+                                       let existing_payment = claimable_payments.insert(payment_hash, ClaimablePayment {
+                                               purpose, htlcs, onion_fields: None,
+                                       });
+                                       if existing_payment.is_some() { return Err(DecodeError::InvalidValue); }
+                               }
                        }
                } else {
                        // LDK versions prior to 0.0.107 did not write a `pending_htlc_purposes`, but do
                        // include a `_legacy_hop_data` in the `OnionPayload`.
-                       for (payment_hash, previous_hops) in claimable_htlcs_list.drain(..) {
-                               if previous_hops.is_empty() {
+                       for (payment_hash, htlcs) in claimable_htlcs_list.drain(..) {
+                               if htlcs.is_empty() {
                                        return Err(DecodeError::InvalidValue);
                                }
-                               let purpose = match &previous_hops[0].onion_payload {
+                               let purpose = match &htlcs[0].onion_payload {
                                        OnionPayload::Invoice { _legacy_hop_data } => {
                                                if let Some(hop_data) = _legacy_hop_data {
                                                        events::PaymentPurpose::InvoicePayment {
@@ -7754,7 +8583,9 @@ where
                                        OnionPayload::Spontaneous(payment_preimage) =>
                                                events::PaymentPurpose::SpontaneousPayment(*payment_preimage),
                                };
-                               claimable_htlcs.insert(payment_hash, (purpose, previous_hops));
+                               claimable_payments.insert(payment_hash, ClaimablePayment {
+                                       purpose, htlcs, onion_fields: None,
+                               });
                        }
                }
 
@@ -7777,25 +8608,25 @@ where
                        let mut peer_state_lock = peer_state_mutex.lock().unwrap();
                        let peer_state = &mut *peer_state_lock;
                        for (chan_id, chan) in peer_state.channel_by_id.iter_mut() {
-                               if chan.outbound_scid_alias() == 0 {
+                               if chan.context.outbound_scid_alias() == 0 {
                                        let mut outbound_scid_alias;
                                        loop {
                                                outbound_scid_alias = fake_scid::Namespace::OutboundAlias
                                                        .get_fake_scid(best_block_height, &genesis_hash, fake_scid_rand_bytes.as_ref().unwrap(), &args.entropy_source);
                                                if outbound_scid_aliases.insert(outbound_scid_alias) { break; }
                                        }
-                                       chan.set_outbound_scid_alias(outbound_scid_alias);
-                               } else if !outbound_scid_aliases.insert(chan.outbound_scid_alias()) {
+                                       chan.context.set_outbound_scid_alias(outbound_scid_alias);
+                               } else if !outbound_scid_aliases.insert(chan.context.outbound_scid_alias()) {
                                        // Note that in rare cases its possible to hit this while reading an older
                                        // channel if we just happened to pick a colliding outbound alias above.
-                                       log_error!(args.logger, "Got duplicate outbound SCID alias; {}", chan.outbound_scid_alias());
+                                       log_error!(args.logger, "Got duplicate outbound SCID alias; {}", chan.context.outbound_scid_alias());
                                        return Err(DecodeError::InvalidValue);
                                }
-                               if chan.is_usable() {
-                                       if short_to_chan_info.insert(chan.outbound_scid_alias(), (chan.get_counterparty_node_id(), *chan_id)).is_some() {
+                               if chan.context.is_usable() {
+                                       if short_to_chan_info.insert(chan.context.outbound_scid_alias(), (chan.context.get_counterparty_node_id(), *chan_id)).is_some() {
                                                // Note that in rare cases its possible to hit this while reading an older
                                                // channel if we just happened to pick a colliding outbound alias above.
-                                               log_error!(args.logger, "Got duplicate outbound SCID alias; {}", chan.outbound_scid_alias());
+                                               log_error!(args.logger, "Got duplicate outbound SCID alias; {}", chan.context.outbound_scid_alias());
                                                return Err(DecodeError::InvalidValue);
                                        }
                                }
@@ -7806,17 +8637,17 @@ where
 
                for (_, monitor) in args.channel_monitors.iter() {
                        for (payment_hash, payment_preimage) in monitor.get_stored_preimages() {
-                               if let Some((payment_purpose, claimable_htlcs)) = claimable_htlcs.remove(&payment_hash) {
+                               if let Some(payment) = claimable_payments.remove(&payment_hash) {
                                        log_info!(args.logger, "Re-claiming HTLCs with payment hash {} as we've released the preimage to a ChannelMonitor!", log_bytes!(payment_hash.0));
                                        let mut claimable_amt_msat = 0;
                                        let mut receiver_node_id = Some(our_network_pubkey);
-                                       let phantom_shared_secret = claimable_htlcs[0].prev_hop.phantom_shared_secret;
+                                       let phantom_shared_secret = payment.htlcs[0].prev_hop.phantom_shared_secret;
                                        if phantom_shared_secret.is_some() {
                                                let phantom_pubkey = args.node_signer.get_node_id(Recipient::PhantomNode)
                                                        .expect("Failed to get node_id for phantom node recipient");
                                                receiver_node_id = Some(phantom_pubkey)
                                        }
-                                       for claimable_htlc in claimable_htlcs {
+                                       for claimable_htlc in payment.htlcs {
                                                claimable_amt_msat += claimable_htlc.value;
 
                                                // Add a holding-cell claim of the payment to the Channel, which should be
@@ -7847,18 +8678,32 @@ where
                                                        previous_hop_monitor.provide_payment_preimage(&payment_hash, &payment_preimage, &args.tx_broadcaster, &bounded_fee_estimator, &args.logger);
                                                }
                                        }
-                                       pending_events_read.push(events::Event::PaymentClaimed {
+                                       pending_events_read.push_back((events::Event::PaymentClaimed {
                                                receiver_node_id,
                                                payment_hash,
-                                               purpose: payment_purpose,
+                                               purpose: payment.purpose,
                                                amount_msat: claimable_amt_msat,
-                                       });
+                                       }, None));
                                }
                        }
                }
 
                for (node_id, monitor_update_blocked_actions) in monitor_update_blocked_actions_per_peer.unwrap() {
-                       if let Some(peer_state) = per_peer_state.get_mut(&node_id) {
+                       if let Some(peer_state) = per_peer_state.get(&node_id) {
+                               for (_, actions) in monitor_update_blocked_actions.iter() {
+                                       for action in actions.iter() {
+                                               if let MonitorUpdateCompletionAction::EmitEventAndFreeOtherChannel {
+                                                       downstream_counterparty_and_funding_outpoint:
+                                                               Some((blocked_node_id, blocked_channel_outpoint, blocking_action)), ..
+                                               } = action {
+                                                       if let Some(blocked_peer_state) = per_peer_state.get(&blocked_node_id) {
+                                                               blocked_peer_state.lock().unwrap().actions_blocking_raa_monitor_updates
+                                                                       .entry(blocked_channel_outpoint.to_channel_id())
+                                                                       .or_insert_with(Vec::new).push(blocking_action.clone());
+                                                       }
+                                               }
+                                       }
+                               }
                                peer_state.lock().unwrap().monitor_update_blocked_actions = monitor_update_blocked_actions;
                        } else {
                                log_error!(args.logger, "Got blocked actions without a per-peer-state for {}", node_id);
@@ -7881,7 +8726,7 @@ where
                        pending_intercepted_htlcs: Mutex::new(pending_intercepted_htlcs.unwrap()),
 
                        forward_htlcs: Mutex::new(forward_htlcs),
-                       claimable_payments: Mutex::new(ClaimablePayments { claimable_htlcs, pending_claiming_payments: pending_claiming_payments.unwrap() }),
+                       claimable_payments: Mutex::new(ClaimablePayments { claimable_payments, pending_claiming_payments: pending_claiming_payments.unwrap() }),
                        outbound_scid_aliases: Mutex::new(outbound_scid_aliases),
                        id_to_peer: Mutex::new(id_to_peer),
                        short_to_chan_info: FairRwLock::new(short_to_chan_info),
@@ -7897,8 +8742,11 @@ where
                        per_peer_state: FairRwLock::new(per_peer_state),
 
                        pending_events: Mutex::new(pending_events_read),
+                       pending_events_processor: AtomicBool::new(false),
                        pending_background_events: Mutex::new(pending_background_events),
                        total_consistency_lock: RwLock::new(()),
+                       #[cfg(debug_assertions)]
+                       background_events_processed_since_startup: AtomicBool::new(false),
                        persistence_notifier: Notifier::new(),
 
                        entropy_source: args.entropy_source,
@@ -7928,19 +8776,18 @@ mod tests {
        use bitcoin::hashes::Hash;
        use bitcoin::hashes::sha256::Hash as Sha256;
        use bitcoin::secp256k1::{PublicKey, Secp256k1, SecretKey};
-       use core::time::Duration;
        use core::sync::atomic::Ordering;
        use crate::events::{Event, HTLCDestination, MessageSendEvent, MessageSendEventsProvider, ClosureReason};
        use crate::ln::{PaymentPreimage, PaymentHash, PaymentSecret};
-       use crate::ln::channelmanager::{inbound_payment, PaymentId, PaymentSendFailure, InterceptId};
+       use crate::ln::channelmanager::{inbound_payment, PaymentId, PaymentSendFailure, RecipientOnionFields, InterceptId};
        use crate::ln::functional_test_utils::*;
        use crate::ln::msgs;
        use crate::ln::msgs::ChannelMessageHandler;
        use crate::routing::router::{PaymentParameters, RouteParameters, find_route};
        use crate::util::errors::APIError;
        use crate::util::test_utils;
-       use crate::util::config::ChannelConfig;
-       use crate::chain::keysinterface::EntropySource;
+       use crate::util::config::{ChannelConfig, ChannelConfigUpdate};
+       use crate::sign::EntropySource;
 
        #[test]
        fn test_notify_limits() {
@@ -7953,9 +8800,9 @@ mod tests {
 
                // All nodes start with a persistable update pending as `create_network` connects each node
                // with all other nodes to make most tests simpler.
-               assert!(nodes[0].node.await_persistable_update_timeout(Duration::from_millis(1)));
-               assert!(nodes[1].node.await_persistable_update_timeout(Duration::from_millis(1)));
-               assert!(nodes[2].node.await_persistable_update_timeout(Duration::from_millis(1)));
+               assert!(nodes[0].node.get_persistable_update_future().poll_is_complete());
+               assert!(nodes[1].node.get_persistable_update_future().poll_is_complete());
+               assert!(nodes[2].node.get_persistable_update_future().poll_is_complete());
 
                let mut chan = create_announced_chan_between_nodes(&nodes, 0, 1);
 
@@ -7969,19 +8816,19 @@ mod tests {
                        &nodes[0].node.get_our_node_id()).pop().unwrap();
 
                // The first two nodes (which opened a channel) should now require fresh persistence
-               assert!(nodes[0].node.await_persistable_update_timeout(Duration::from_millis(1)));
-               assert!(nodes[1].node.await_persistable_update_timeout(Duration::from_millis(1)));
+               assert!(nodes[0].node.get_persistable_update_future().poll_is_complete());
+               assert!(nodes[1].node.get_persistable_update_future().poll_is_complete());
                // ... but the last node should not.
-               assert!(!nodes[2].node.await_persistable_update_timeout(Duration::from_millis(1)));
+               assert!(!nodes[2].node.get_persistable_update_future().poll_is_complete());
                // After persisting the first two nodes they should no longer need fresh persistence.
-               assert!(!nodes[0].node.await_persistable_update_timeout(Duration::from_millis(1)));
-               assert!(!nodes[1].node.await_persistable_update_timeout(Duration::from_millis(1)));
+               assert!(!nodes[0].node.get_persistable_update_future().poll_is_complete());
+               assert!(!nodes[1].node.get_persistable_update_future().poll_is_complete());
 
                // Node 3, unrelated to the only channel, shouldn't care if it receives a channel_update
                // about the channel.
                nodes[2].node.handle_channel_update(&nodes[1].node.get_our_node_id(), &chan.0);
                nodes[2].node.handle_channel_update(&nodes[1].node.get_our_node_id(), &chan.1);
-               assert!(!nodes[2].node.await_persistable_update_timeout(Duration::from_millis(1)));
+               assert!(!nodes[2].node.get_persistable_update_future().poll_is_complete());
 
                // The nodes which are a party to the channel should also ignore messages from unrelated
                // parties.
@@ -7989,8 +8836,8 @@ mod tests {
                nodes[0].node.handle_channel_update(&nodes[2].node.get_our_node_id(), &chan.1);
                nodes[1].node.handle_channel_update(&nodes[2].node.get_our_node_id(), &chan.0);
                nodes[1].node.handle_channel_update(&nodes[2].node.get_our_node_id(), &chan.1);
-               assert!(!nodes[0].node.await_persistable_update_timeout(Duration::from_millis(1)));
-               assert!(!nodes[1].node.await_persistable_update_timeout(Duration::from_millis(1)));
+               assert!(!nodes[0].node.get_persistable_update_future().poll_is_complete());
+               assert!(!nodes[1].node.get_persistable_update_future().poll_is_complete());
 
                // At this point the channel info given by peers should still be the same.
                assert_eq!(nodes[0].node.list_channels()[0], node_a_chan_info);
@@ -8007,8 +8854,8 @@ mod tests {
                // persisted and that its channel info remains the same.
                nodes[0].node.handle_channel_update(&nodes[1].node.get_our_node_id(), &as_update);
                nodes[1].node.handle_channel_update(&nodes[0].node.get_our_node_id(), &bs_update);
-               assert!(!nodes[0].node.await_persistable_update_timeout(Duration::from_millis(1)));
-               assert!(!nodes[1].node.await_persistable_update_timeout(Duration::from_millis(1)));
+               assert!(!nodes[0].node.get_persistable_update_future().poll_is_complete());
+               assert!(!nodes[1].node.get_persistable_update_future().poll_is_complete());
                assert_eq!(nodes[0].node.list_channels()[0], node_a_chan_info);
                assert_eq!(nodes[1].node.list_channels()[0], node_b_chan_info);
 
@@ -8016,8 +8863,8 @@ mod tests {
                // the channel info has updated.
                nodes[0].node.handle_channel_update(&nodes[1].node.get_our_node_id(), &bs_update);
                nodes[1].node.handle_channel_update(&nodes[0].node.get_our_node_id(), &as_update);
-               assert!(nodes[0].node.await_persistable_update_timeout(Duration::from_millis(1)));
-               assert!(nodes[1].node.await_persistable_update_timeout(Duration::from_millis(1)));
+               assert!(nodes[0].node.get_persistable_update_future().poll_is_complete());
+               assert!(nodes[1].node.get_persistable_update_future().poll_is_complete());
                assert_ne!(nodes[0].node.list_channels()[0], node_a_chan_info);
                assert_ne!(nodes[1].node.list_channels()[0], node_b_chan_info);
        }
@@ -8041,15 +8888,18 @@ mod tests {
                // Use the utility function send_payment_along_path to send the payment with MPP data which
                // indicates there are more HTLCs coming.
                let cur_height = CHAN_CONFIRM_DEPTH + 1; // route_payment calls send_payment, which adds 1 to the current height. So we do the same here to match.
-               let session_privs = nodes[0].node.test_add_new_pending_payment(our_payment_hash, Some(payment_secret), payment_id, &mpp_route).unwrap();
-               nodes[0].node.test_send_payment_along_path(&mpp_route.paths[0], &our_payment_hash, &Some(payment_secret), 200_000, cur_height, payment_id, &None, session_privs[0]).unwrap();
+               let session_privs = nodes[0].node.test_add_new_pending_payment(our_payment_hash,
+                       RecipientOnionFields::secret_only(payment_secret), payment_id, &mpp_route).unwrap();
+               nodes[0].node.test_send_payment_along_path(&mpp_route.paths[0], &our_payment_hash,
+                       RecipientOnionFields::secret_only(payment_secret), 200_000, cur_height, payment_id, &None, session_privs[0]).unwrap();
                check_added_monitors!(nodes[0], 1);
                let mut events = nodes[0].node.get_and_clear_pending_msg_events();
                assert_eq!(events.len(), 1);
                pass_along_path(&nodes[0], &[&nodes[1]], 200_000, our_payment_hash, Some(payment_secret), events.drain(..).next().unwrap(), false, None);
 
                // Next, send a keysend payment with the same payment_hash and make sure it fails.
-               nodes[0].node.send_spontaneous_payment(&route, Some(payment_preimage), PaymentId(payment_preimage.0)).unwrap();
+               nodes[0].node.send_spontaneous_payment(&route, Some(payment_preimage),
+                       RecipientOnionFields::spontaneous_empty(), PaymentId(payment_preimage.0)).unwrap();
                check_added_monitors!(nodes[0], 1);
                let mut events = nodes[0].node.get_and_clear_pending_msg_events();
                assert_eq!(events.len(), 1);
@@ -8072,7 +8922,8 @@ mod tests {
                expect_payment_failed!(nodes[0], our_payment_hash, true);
 
                // Send the second half of the original MPP payment.
-               nodes[0].node.test_send_payment_along_path(&mpp_route.paths[1], &our_payment_hash, &Some(payment_secret), 200_000, cur_height, payment_id, &None, session_privs[1]).unwrap();
+               nodes[0].node.test_send_payment_along_path(&mpp_route.paths[1], &our_payment_hash,
+                       RecipientOnionFields::secret_only(payment_secret), 200_000, cur_height, payment_id, &None, session_privs[1]).unwrap();
                check_added_monitors!(nodes[0], 1);
                let mut events = nodes[0].node.get_and_clear_pending_msg_events();
                assert_eq!(events.len(), 1);
@@ -8144,13 +8995,26 @@ mod tests {
 
        #[test]
        fn test_keysend_dup_payment_hash() {
+               do_test_keysend_dup_payment_hash(false);
+               do_test_keysend_dup_payment_hash(true);
+       }
+
+       fn do_test_keysend_dup_payment_hash(accept_mpp_keysend: bool) {
                // (1): Test that a keysend payment with a duplicate payment hash to an existing pending
                //      outbound regular payment fails as expected.
                // (2): Test that a regular payment with a duplicate payment hash to an existing keysend payment
                //      fails as expected.
+               // (3): Test that a keysend payment with a duplicate payment hash to an existing keysend
+               //      payment fails as expected. When `accept_mpp_keysend` is false, this tests that we
+               //      reject MPP keysend payments, since in this case where the payment has no payment
+               //      secret, a keysend payment with a duplicate hash is basically an MPP keysend. If
+               //      `accept_mpp_keysend` is true, this tests that we only accept MPP keysends with
+               //      payment secrets and reject otherwise.
                let chanmon_cfgs = create_chanmon_cfgs(2);
                let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
-               let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
+               let mut mpp_keysend_cfg = test_default_channel_config();
+               mpp_keysend_cfg.accept_mpp_keysend = accept_mpp_keysend;
+               let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, Some(mpp_keysend_cfg)]);
                let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
                create_announced_chan_between_nodes(&nodes, 0, 1);
                let scorer = test_utils::TestScorer::new();
@@ -8162,14 +9026,15 @@ mod tests {
 
                // Next, attempt a keysend payment and make sure it fails.
                let route_params = RouteParameters {
-                       payment_params: PaymentParameters::for_keysend(expected_route.last().unwrap().node.get_our_node_id(), TEST_FINAL_CLTV),
+                       payment_params: PaymentParameters::for_keysend(expected_route.last().unwrap().node.get_our_node_id(), TEST_FINAL_CLTV, false),
                        final_value_msat: 100_000,
                };
                let route = find_route(
                        &nodes[0].node.get_our_node_id(), &route_params, &nodes[0].network_graph,
-                       None, nodes[0].logger, &scorer, &random_seed_bytes
+                       None, nodes[0].logger, &scorer, &(), &random_seed_bytes
                ).unwrap();
-               nodes[0].node.send_spontaneous_payment(&route, Some(payment_preimage), PaymentId(payment_preimage.0)).unwrap();
+               nodes[0].node.send_spontaneous_payment(&route, Some(payment_preimage),
+                       RecipientOnionFields::spontaneous_empty(), PaymentId(payment_preimage.0)).unwrap();
                check_added_monitors!(nodes[0], 1);
                let mut events = nodes[0].node.get_and_clear_pending_msg_events();
                assert_eq!(events.len(), 1);
@@ -8200,9 +9065,10 @@ mod tests {
                let payment_preimage = PaymentPreimage([42; 32]);
                let route = find_route(
                        &nodes[0].node.get_our_node_id(), &route_params, &nodes[0].network_graph,
-                       None, nodes[0].logger, &scorer, &random_seed_bytes
+                       None, nodes[0].logger, &scorer, &(), &random_seed_bytes
                ).unwrap();
-               let payment_hash = nodes[0].node.send_spontaneous_payment(&route, Some(payment_preimage), PaymentId(payment_preimage.0)).unwrap();
+               let payment_hash = nodes[0].node.send_spontaneous_payment(&route, Some(payment_preimage),
+                       RecipientOnionFields::spontaneous_empty(), PaymentId(payment_preimage.0)).unwrap();
                check_added_monitors!(nodes[0], 1);
                let mut events = nodes[0].node.get_and_clear_pending_msg_events();
                assert_eq!(events.len(), 1);
@@ -8212,7 +9078,8 @@ mod tests {
 
                // Next, attempt a regular payment and make sure it fails.
                let payment_secret = PaymentSecret([43; 32]);
-               nodes[0].node.send_payment(&route, payment_hash, &Some(payment_secret), PaymentId(payment_hash.0)).unwrap();
+               nodes[0].node.send_payment_with_route(&route, payment_hash,
+                       RecipientOnionFields::secret_only(payment_secret), PaymentId(payment_hash.0)).unwrap();
                check_added_monitors!(nodes[0], 1);
                let mut events = nodes[0].node.get_and_clear_pending_msg_events();
                assert_eq!(events.len(), 1);
@@ -8236,6 +9103,53 @@ mod tests {
 
                // Finally, succeed the keysend payment.
                claim_payment(&nodes[0], &expected_route, payment_preimage);
+
+               // To start (3), send a keysend payment but don't claim it.
+               let payment_id_1 = PaymentId([44; 32]);
+               let payment_hash = nodes[0].node.send_spontaneous_payment(&route, Some(payment_preimage),
+                       RecipientOnionFields::spontaneous_empty(), payment_id_1).unwrap();
+               check_added_monitors!(nodes[0], 1);
+               let mut events = nodes[0].node.get_and_clear_pending_msg_events();
+               assert_eq!(events.len(), 1);
+               let event = events.pop().unwrap();
+               let path = vec![&nodes[1]];
+               pass_along_path(&nodes[0], &path, 100_000, payment_hash, None, event, true, Some(payment_preimage));
+
+               // Next, attempt a keysend payment and make sure it fails.
+               let route_params = RouteParameters {
+                       payment_params: PaymentParameters::for_keysend(expected_route.last().unwrap().node.get_our_node_id(), TEST_FINAL_CLTV, false),
+                       final_value_msat: 100_000,
+               };
+               let route = find_route(
+                       &nodes[0].node.get_our_node_id(), &route_params, &nodes[0].network_graph,
+                       None, nodes[0].logger, &scorer, &(), &random_seed_bytes
+               ).unwrap();
+               let payment_id_2 = PaymentId([45; 32]);
+               nodes[0].node.send_spontaneous_payment(&route, Some(payment_preimage),
+                       RecipientOnionFields::spontaneous_empty(), payment_id_2).unwrap();
+               check_added_monitors!(nodes[0], 1);
+               let mut events = nodes[0].node.get_and_clear_pending_msg_events();
+               assert_eq!(events.len(), 1);
+               let ev = events.drain(..).next().unwrap();
+               let payment_event = SendEvent::from_event(ev);
+               nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &payment_event.msgs[0]);
+               check_added_monitors!(nodes[1], 0);
+               commitment_signed_dance!(nodes[1], nodes[0], payment_event.commitment_msg, false);
+               expect_pending_htlcs_forwardable!(nodes[1]);
+               expect_pending_htlcs_forwardable_and_htlc_handling_failed!(nodes[1], vec![HTLCDestination::FailedPayment { payment_hash }]);
+               check_added_monitors!(nodes[1], 1);
+               let updates = get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id());
+               assert!(updates.update_add_htlcs.is_empty());
+               assert!(updates.update_fulfill_htlcs.is_empty());
+               assert_eq!(updates.update_fail_htlcs.len(), 1);
+               assert!(updates.update_fail_malformed_htlcs.is_empty());
+               assert!(updates.update_fee.is_none());
+               nodes[0].node.handle_update_fail_htlc(&nodes[1].node.get_our_node_id(), &updates.update_fail_htlcs[0]);
+               commitment_signed_dance!(nodes[0], nodes[1], updates.commitment_signed, true, true);
+               expect_payment_failed!(nodes[0], payment_hash, true);
+
+               // Finally, claim the original payment.
+               claim_payment(&nodes[0], &expected_route, payment_preimage);
        }
 
        #[test]
@@ -8252,7 +9166,7 @@ mod tests {
 
                let _chan = create_chan_between_nodes(&nodes[0], &nodes[1]);
                let route_params = RouteParameters {
-                       payment_params: PaymentParameters::for_keysend(payee_pubkey, 40),
+                       payment_params: PaymentParameters::for_keysend(payee_pubkey, 40, false),
                        final_value_msat: 10_000,
                };
                let network_graph = nodes[0].network_graph.clone();
@@ -8261,13 +9175,15 @@ mod tests {
                let random_seed_bytes = chanmon_cfgs[1].keys_manager.get_secure_random_bytes();
                let route = find_route(
                        &payer_pubkey, &route_params, &network_graph, Some(&first_hops.iter().collect::<Vec<_>>()),
-                       nodes[0].logger, &scorer, &random_seed_bytes
+                       nodes[0].logger, &scorer, &(), &random_seed_bytes
                ).unwrap();
 
                let test_preimage = PaymentPreimage([42; 32]);
                let mismatch_payment_hash = PaymentHash([43; 32]);
-               let session_privs = nodes[0].node.test_add_new_pending_payment(mismatch_payment_hash, None, PaymentId(mismatch_payment_hash.0), &route).unwrap();
-               nodes[0].node.test_send_payment_internal(&route, mismatch_payment_hash, &None, Some(test_preimage), PaymentId(mismatch_payment_hash.0), None, session_privs).unwrap();
+               let session_privs = nodes[0].node.test_add_new_pending_payment(mismatch_payment_hash,
+                       RecipientOnionFields::spontaneous_empty(), PaymentId(mismatch_payment_hash.0), &route).unwrap();
+               nodes[0].node.test_send_payment_internal(&route, mismatch_payment_hash,
+                       RecipientOnionFields::spontaneous_empty(), Some(test_preimage), PaymentId(mismatch_payment_hash.0), None, session_privs).unwrap();
                check_added_monitors!(nodes[0], 1);
 
                let updates = get_htlc_update_msgs!(nodes[0], nodes[1].node.get_our_node_id());
@@ -8283,10 +9199,13 @@ mod tests {
 
        #[test]
        fn test_keysend_msg_with_secret_err() {
-               // Test that we error as expected if we receive a keysend payment that includes a payment secret.
+               // Test that we error as expected if we receive a keysend payment that includes a payment
+               // secret when we don't support MPP keysend.
+               let mut reject_mpp_keysend_cfg = test_default_channel_config();
+               reject_mpp_keysend_cfg.accept_mpp_keysend = false;
                let chanmon_cfgs = create_chanmon_cfgs(2);
                let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
-               let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
+               let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, Some(reject_mpp_keysend_cfg)]);
                let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
 
                let payer_pubkey = nodes[0].node.get_our_node_id();
@@ -8294,7 +9213,7 @@ mod tests {
 
                let _chan = create_chan_between_nodes(&nodes[0], &nodes[1]);
                let route_params = RouteParameters {
-                       payment_params: PaymentParameters::for_keysend(payee_pubkey, 40),
+                       payment_params: PaymentParameters::for_keysend(payee_pubkey, 40, false),
                        final_value_msat: 10_000,
                };
                let network_graph = nodes[0].network_graph.clone();
@@ -8303,14 +9222,17 @@ mod tests {
                let random_seed_bytes = chanmon_cfgs[1].keys_manager.get_secure_random_bytes();
                let route = find_route(
                        &payer_pubkey, &route_params, &network_graph, Some(&first_hops.iter().collect::<Vec<_>>()),
-                       nodes[0].logger, &scorer, &random_seed_bytes
+                       nodes[0].logger, &scorer, &(), &random_seed_bytes
                ).unwrap();
 
                let test_preimage = PaymentPreimage([42; 32]);
                let test_secret = PaymentSecret([43; 32]);
                let payment_hash = PaymentHash(Sha256::hash(&test_preimage.0).into_inner());
-               let session_privs = nodes[0].node.test_add_new_pending_payment(payment_hash, Some(test_secret), PaymentId(payment_hash.0), &route).unwrap();
-               nodes[0].node.test_send_payment_internal(&route, payment_hash, &Some(test_secret), Some(test_preimage), PaymentId(payment_hash.0), None, session_privs).unwrap();
+               let session_privs = nodes[0].node.test_add_new_pending_payment(payment_hash,
+                       RecipientOnionFields::secret_only(test_secret), PaymentId(payment_hash.0), &route).unwrap();
+               nodes[0].node.test_send_payment_internal(&route, payment_hash,
+                       RecipientOnionFields::secret_only(test_secret), Some(test_preimage),
+                       PaymentId(payment_hash.0), None, session_privs).unwrap();
                check_added_monitors!(nodes[0], 1);
 
                let updates = get_htlc_update_msgs!(nodes[0], nodes[1].node.get_our_node_id());
@@ -8340,14 +9262,16 @@ mod tests {
                let (mut route, payment_hash, _, _) = get_route_and_payment_hash!(&nodes[0], nodes[3], 100000);
                let path = route.paths[0].clone();
                route.paths.push(path);
-               route.paths[0][0].pubkey = nodes[1].node.get_our_node_id();
-               route.paths[0][0].short_channel_id = chan_1_id;
-               route.paths[0][1].short_channel_id = chan_3_id;
-               route.paths[1][0].pubkey = nodes[2].node.get_our_node_id();
-               route.paths[1][0].short_channel_id = chan_2_id;
-               route.paths[1][1].short_channel_id = chan_4_id;
-
-               match nodes[0].node.send_payment(&route, payment_hash, &None, PaymentId(payment_hash.0)).unwrap_err() {
+               route.paths[0].hops[0].pubkey = nodes[1].node.get_our_node_id();
+               route.paths[0].hops[0].short_channel_id = chan_1_id;
+               route.paths[0].hops[1].short_channel_id = chan_3_id;
+               route.paths[1].hops[0].pubkey = nodes[2].node.get_our_node_id();
+               route.paths[1].hops[0].short_channel_id = chan_2_id;
+               route.paths[1].hops[1].short_channel_id = chan_4_id;
+
+               match nodes[0].node.send_payment_with_route(&route, payment_hash,
+                       RecipientOnionFields::spontaneous_empty(), PaymentId(payment_hash.0))
+               .unwrap_err() {
                        PaymentSendFailure::ParameterError(APIError::APIMisuseError { ref err }) => {
                                assert!(regex::Regex::new(r"Payment secret is required for multi-path payments").unwrap().is_match(err))
                        },
@@ -8462,6 +9386,7 @@ mod tests {
                        assert_eq!(nodes_0_lock.len(), 1);
                        assert!(nodes_0_lock.contains_key(channel_id));
                }
+               expect_channel_pending_event(&nodes[1], &nodes[0].node.get_our_node_id());
 
                {
                        // Assert that `nodes[1]`'s `id_to_peer` map is populated with the channel as soon as
@@ -8474,6 +9399,7 @@ mod tests {
                let funding_signed = get_event_msg!(nodes[1], MessageSendEvent::SendFundingSigned, nodes[0].node.get_our_node_id());
                nodes[0].node.handle_funding_signed(&nodes[1].node.get_our_node_id(), &funding_signed);
                check_added_monitors!(nodes[0], 1);
+               expect_channel_pending_event(&nodes[0], &nodes[1].node.get_our_node_id());
                let (channel_ready, _) = create_chan_between_nodes_with_value_confirm(&nodes[0], &nodes[1], &tx);
                let (announcement, nodes_0_update, nodes_1_update) = create_chan_between_nodes_with_value_b(&nodes[0], &nodes[1], &channel_ready);
                update_nodes_with_chan_announce(&nodes, 0, 1, &announcement, &nodes_0_update, &nodes_1_update);
@@ -8616,10 +9542,13 @@ mod tests {
 
                                nodes[1].node.handle_funding_created(&nodes[0].node.get_our_node_id(), &funding_created_msg);
                                check_added_monitors!(nodes[1], 1);
+                               expect_channel_pending_event(&nodes[1], &nodes[0].node.get_our_node_id());
+
                                let funding_signed = get_event_msg!(nodes[1], MessageSendEvent::SendFundingSigned, nodes[0].node.get_our_node_id());
 
                                nodes[0].node.handle_funding_signed(&nodes[1].node.get_our_node_id(), &funding_signed);
                                check_added_monitors!(nodes[0], 1);
+                               expect_channel_pending_event(&nodes[0], &nodes[1].node.get_our_node_id());
                        }
                        open_channel_msg.temporary_channel_id = nodes[0].keys_manager.get_secure_random_bytes();
                }
@@ -8639,12 +9568,14 @@ mod tests {
                                &SecretKey::from_slice(&nodes[1].keys_manager.get_secure_random_bytes()).unwrap());
                        peer_pks.push(random_pk);
                        nodes[1].node.peer_connected(&random_pk, &msgs::Init {
-                               features: nodes[0].node.init_features(), remote_network_address: None }, true).unwrap();
+                               features: nodes[0].node.init_features(), networks: None, remote_network_address: None
+                       }, true).unwrap();
                }
                let last_random_pk = PublicKey::from_secret_key(&nodes[0].node.secp_ctx,
                        &SecretKey::from_slice(&nodes[1].keys_manager.get_secure_random_bytes()).unwrap());
                nodes[1].node.peer_connected(&last_random_pk, &msgs::Init {
-                       features: nodes[0].node.init_features(), remote_network_address: None }, true).unwrap_err();
+                       features: nodes[0].node.init_features(), networks: None, remote_network_address: None
+               }, true).unwrap_err();
 
                // Also importantly, because nodes[0] isn't "protected", we will refuse a reconnection from
                // them if we have too many un-channel'd peers.
@@ -8655,13 +9586,16 @@ mod tests {
                        if let Event::ChannelClosed { .. } = ev { } else { panic!(); }
                }
                nodes[1].node.peer_connected(&last_random_pk, &msgs::Init {
-                       features: nodes[0].node.init_features(), remote_network_address: None }, true).unwrap();
+                       features: nodes[0].node.init_features(), networks: None, remote_network_address: None
+               }, true).unwrap();
                nodes[1].node.peer_connected(&nodes[0].node.get_our_node_id(), &msgs::Init {
-                       features: nodes[0].node.init_features(), remote_network_address: None }, true).unwrap_err();
+                       features: nodes[0].node.init_features(), networks: None, remote_network_address: None
+               }, true).unwrap_err();
 
                // but of course if the connection is outbound its allowed...
                nodes[1].node.peer_connected(&nodes[0].node.get_our_node_id(), &msgs::Init {
-                       features: nodes[0].node.init_features(), remote_network_address: None }, false).unwrap();
+                       features: nodes[0].node.init_features(), networks: None, remote_network_address: None
+               }, false).unwrap();
                nodes[1].node.peer_disconnected(&nodes[0].node.get_our_node_id());
 
                // Now nodes[0] is disconnected but still has a pending, un-funded channel lying around.
@@ -8685,7 +9619,8 @@ mod tests {
                // "protected" and can connect again.
                mine_transaction(&nodes[1], funding_tx.as_ref().unwrap());
                nodes[1].node.peer_connected(&nodes[0].node.get_our_node_id(), &msgs::Init {
-                       features: nodes[0].node.init_features(), remote_network_address: None }, true).unwrap();
+                       features: nodes[0].node.init_features(), networks: None, remote_network_address: None
+               }, true).unwrap();
                get_event_msg!(nodes[1], MessageSendEvent::SendChannelReestablish, nodes[0].node.get_our_node_id());
 
                // Further, because the first channel was funded, we can open another channel with
@@ -8750,7 +9685,8 @@ mod tests {
                        let random_pk = PublicKey::from_secret_key(&nodes[0].node.secp_ctx,
                                &SecretKey::from_slice(&nodes[1].keys_manager.get_secure_random_bytes()).unwrap());
                        nodes[1].node.peer_connected(&random_pk, &msgs::Init {
-                               features: nodes[0].node.init_features(), remote_network_address: None }, true).unwrap();
+                               features: nodes[0].node.init_features(), networks: None, remote_network_address: None
+                       }, true).unwrap();
 
                        nodes[1].node.handle_open_channel(&random_pk, &open_channel_msg);
                        let events = nodes[1].node.get_and_clear_pending_events();
@@ -8768,7 +9704,8 @@ mod tests {
                let last_random_pk = PublicKey::from_secret_key(&nodes[0].node.secp_ctx,
                        &SecretKey::from_slice(&nodes[1].keys_manager.get_secure_random_bytes()).unwrap());
                nodes[1].node.peer_connected(&last_random_pk, &msgs::Init {
-                       features: nodes[0].node.init_features(), remote_network_address: None }, true).unwrap();
+                       features: nodes[0].node.init_features(), networks: None, remote_network_address: None
+               }, true).unwrap();
                nodes[1].node.handle_open_channel(&last_random_pk, &open_channel_msg);
                let events = nodes[1].node.get_and_clear_pending_events();
                match events[0] {
@@ -8831,19 +9768,75 @@ mod tests {
 
                check_closed_event!(nodes[1], 1, ClosureReason::HolderForceClosed);
        }
+
+       #[test]
+       fn test_update_channel_config() {
+               let chanmon_cfg = create_chanmon_cfgs(2);
+               let node_cfg = create_node_cfgs(2, &chanmon_cfg);
+               let mut user_config = test_default_channel_config();
+               let node_chanmgr = create_node_chanmgrs(2, &node_cfg, &[Some(user_config), Some(user_config)]);
+               let nodes = create_network(2, &node_cfg, &node_chanmgr);
+               let _ = create_announced_chan_between_nodes(&nodes, 0, 1);
+               let channel = &nodes[0].node.list_channels()[0];
+
+               nodes[0].node.update_channel_config(&channel.counterparty.node_id, &[channel.channel_id], &user_config.channel_config).unwrap();
+               let events = nodes[0].node.get_and_clear_pending_msg_events();
+               assert_eq!(events.len(), 0);
+
+               user_config.channel_config.forwarding_fee_base_msat += 10;
+               nodes[0].node.update_channel_config(&channel.counterparty.node_id, &[channel.channel_id], &user_config.channel_config).unwrap();
+               assert_eq!(nodes[0].node.list_channels()[0].config.unwrap().forwarding_fee_base_msat, user_config.channel_config.forwarding_fee_base_msat);
+               let events = nodes[0].node.get_and_clear_pending_msg_events();
+               assert_eq!(events.len(), 1);
+               match &events[0] {
+                       MessageSendEvent::BroadcastChannelUpdate { .. } => {},
+                       _ => panic!("expected BroadcastChannelUpdate event"),
+               }
+
+               nodes[0].node.update_partial_channel_config(&channel.counterparty.node_id, &[channel.channel_id], &ChannelConfigUpdate::default()).unwrap();
+               let events = nodes[0].node.get_and_clear_pending_msg_events();
+               assert_eq!(events.len(), 0);
+
+               let new_cltv_expiry_delta = user_config.channel_config.cltv_expiry_delta + 6;
+               nodes[0].node.update_partial_channel_config(&channel.counterparty.node_id, &[channel.channel_id], &ChannelConfigUpdate {
+                       cltv_expiry_delta: Some(new_cltv_expiry_delta),
+                       ..Default::default()
+               }).unwrap();
+               assert_eq!(nodes[0].node.list_channels()[0].config.unwrap().cltv_expiry_delta, new_cltv_expiry_delta);
+               let events = nodes[0].node.get_and_clear_pending_msg_events();
+               assert_eq!(events.len(), 1);
+               match &events[0] {
+                       MessageSendEvent::BroadcastChannelUpdate { .. } => {},
+                       _ => panic!("expected BroadcastChannelUpdate event"),
+               }
+
+               let new_fee = user_config.channel_config.forwarding_fee_proportional_millionths + 100;
+               nodes[0].node.update_partial_channel_config(&channel.counterparty.node_id, &[channel.channel_id], &ChannelConfigUpdate {
+                       forwarding_fee_proportional_millionths: Some(new_fee),
+                       ..Default::default()
+               }).unwrap();
+               assert_eq!(nodes[0].node.list_channels()[0].config.unwrap().cltv_expiry_delta, new_cltv_expiry_delta);
+               assert_eq!(nodes[0].node.list_channels()[0].config.unwrap().forwarding_fee_proportional_millionths, new_fee);
+               let events = nodes[0].node.get_and_clear_pending_msg_events();
+               assert_eq!(events.len(), 1);
+               match &events[0] {
+                       MessageSendEvent::BroadcastChannelUpdate { .. } => {},
+                       _ => panic!("expected BroadcastChannelUpdate event"),
+               }
+       }
 }
 
-#[cfg(all(any(test, feature = "_test_utils"), feature = "_bench_unstable"))]
+#[cfg(ldk_bench)]
 pub mod bench {
        use crate::chain::Listen;
        use crate::chain::chainmonitor::{ChainMonitor, Persist};
-       use crate::chain::keysinterface::{EntropySource, KeysManager, InMemorySigner};
+       use crate::sign::{KeysManager, InMemorySigner};
        use crate::events::{Event, MessageSendEvent, MessageSendEventsProvider};
-       use crate::ln::channelmanager::{self, BestBlock, ChainParameters, ChannelManager, PaymentHash, PaymentPreimage, PaymentId};
+       use crate::ln::channelmanager::{BestBlock, ChainParameters, ChannelManager, PaymentHash, PaymentPreimage, PaymentId, RecipientOnionFields, Retry};
        use crate::ln::functional_test_utils::*;
        use crate::ln::msgs::{ChannelMessageHandler, Init};
        use crate::routing::gossip::NetworkGraph;
-       use crate::routing::router::{PaymentParameters, get_route};
+       use crate::routing::router::{PaymentParameters, RouteParameters};
        use crate::util::test_utils;
        use crate::util::config::UserConfig;
 
@@ -8853,31 +9846,38 @@ pub mod bench {
 
        use crate::sync::{Arc, Mutex};
 
-       use test::Bencher;
+       use criterion::Criterion;
+
+       type Manager<'a, P> = ChannelManager<
+               &'a ChainMonitor<InMemorySigner, &'a test_utils::TestChainSource,
+                       &'a test_utils::TestBroadcaster, &'a test_utils::TestFeeEstimator,
+                       &'a test_utils::TestLogger, &'a P>,
+               &'a test_utils::TestBroadcaster, &'a KeysManager, &'a KeysManager, &'a KeysManager,
+               &'a test_utils::TestFeeEstimator, &'a test_utils::TestRouter<'a>,
+               &'a test_utils::TestLogger>;
 
-       struct NodeHolder<'a, P: Persist<InMemorySigner>> {
-               node: &'a ChannelManager<
-                       &'a ChainMonitor<InMemorySigner, &'a test_utils::TestChainSource,
-                               &'a test_utils::TestBroadcaster, &'a test_utils::TestFeeEstimator,
-                               &'a test_utils::TestLogger, &'a P>,
-                       &'a test_utils::TestBroadcaster, &'a KeysManager, &'a KeysManager, &'a KeysManager,
-                       &'a test_utils::TestFeeEstimator, &'a test_utils::TestRouter<'a>,
-                       &'a test_utils::TestLogger>,
+       struct ANodeHolder<'a, P: Persist<InMemorySigner>> {
+               node: &'a Manager<'a, P>,
+       }
+       impl<'a, P: Persist<InMemorySigner>> NodeHolder for ANodeHolder<'a, P> {
+               type CM = Manager<'a, P>;
+               #[inline]
+               fn node(&self) -> &Manager<'a, P> { self.node }
+               #[inline]
+               fn chain_monitor(&self) -> Option<&test_utils::TestChainMonitor> { None }
        }
 
-       #[cfg(test)]
-       #[bench]
-       fn bench_sends(bench: &mut Bencher) {
-               bench_two_sends(bench, test_utils::TestPersister::new(), test_utils::TestPersister::new());
+       pub fn bench_sends(bench: &mut Criterion) {
+               bench_two_sends(bench, "bench_sends", test_utils::TestPersister::new(), test_utils::TestPersister::new());
        }
 
-       pub fn bench_two_sends<P: Persist<InMemorySigner>>(bench: &mut Bencher, persister_a: P, persister_b: P) {
+       pub fn bench_two_sends<P: Persist<InMemorySigner>>(bench: &mut Criterion, bench_name: &str, persister_a: P, persister_b: P) {
                // Do a simple benchmark of sending a payment back and forth between two nodes.
                // Note that this is unrealistic as each payment send will require at least two fsync
                // calls per node.
                let network = bitcoin::Network::Testnet;
 
-               let tx_broadcaster = test_utils::TestBroadcaster{txn_broadcasted: Mutex::new(Vec::new()), blocks: Arc::new(Mutex::new(Vec::new()))};
+               let tx_broadcaster = test_utils::TestBroadcaster::new(network);
                let fee_estimator = test_utils::TestFeeEstimator { sat_per_kw: Mutex::new(253) };
                let logger_a = test_utils::TestLogger::with_id("node a".to_owned());
                let scorer = Mutex::new(test_utils::TestScorer::new());
@@ -8893,7 +9893,7 @@ pub mod bench {
                        network,
                        best_block: BestBlock::from_network(network),
                });
-               let node_a_holder = NodeHolder { node: &node_a };
+               let node_a_holder = ANodeHolder { node: &node_a };
 
                let logger_b = test_utils::TestLogger::with_id("node a".to_owned());
                let chain_monitor_b = ChainMonitor::new(None, &tx_broadcaster, &logger_a, &fee_estimator, &persister_b);
@@ -8903,10 +9903,14 @@ pub mod bench {
                        network,
                        best_block: BestBlock::from_network(network),
                });
-               let node_b_holder = NodeHolder { node: &node_b };
-
-               node_a.peer_connected(&node_b.get_our_node_id(), &Init { features: node_b.init_features(), remote_network_address: None }, true).unwrap();
-               node_b.peer_connected(&node_a.get_our_node_id(), &Init { features: node_a.init_features(), remote_network_address: None }, false).unwrap();
+               let node_b_holder = ANodeHolder { node: &node_b };
+
+               node_a.peer_connected(&node_b.get_our_node_id(), &Init {
+                       features: node_b.init_features(), networks: None, remote_network_address: None
+               }, true).unwrap();
+               node_b.peer_connected(&node_a.get_our_node_id(), &Init {
+                       features: node_a.init_features(), networks: None, remote_network_address: None
+               }, false).unwrap();
                node_a.create_channel(node_b.get_our_node_id(), 8_000_000, 100_000_000, 42, None).unwrap();
                node_b.handle_open_channel(&node_a.get_our_node_id(), &get_event_msg!(node_a_holder, MessageSendEvent::SendOpenChannel, node_b.get_our_node_id()));
                node_a.handle_accept_channel(&node_b.get_our_node_id(), &get_event_msg!(node_b_holder, MessageSendEvent::SendAcceptChannel, node_a.get_our_node_id()));
@@ -8920,14 +9924,28 @@ pub mod bench {
                } else { panic!(); }
 
                node_b.handle_funding_created(&node_a.get_our_node_id(), &get_event_msg!(node_a_holder, MessageSendEvent::SendFundingCreated, node_b.get_our_node_id()));
+               let events_b = node_b.get_and_clear_pending_events();
+               assert_eq!(events_b.len(), 1);
+               match events_b[0] {
+                       Event::ChannelPending{ ref counterparty_node_id, .. } => {
+                               assert_eq!(*counterparty_node_id, node_a.get_our_node_id());
+                       },
+                       _ => panic!("Unexpected event"),
+               }
+
                node_a.handle_funding_signed(&node_b.get_our_node_id(), &get_event_msg!(node_b_holder, MessageSendEvent::SendFundingSigned, node_a.get_our_node_id()));
+               let events_a = node_a.get_and_clear_pending_events();
+               assert_eq!(events_a.len(), 1);
+               match events_a[0] {
+                       Event::ChannelPending{ ref counterparty_node_id, .. } => {
+                               assert_eq!(*counterparty_node_id, node_b.get_our_node_id());
+                       },
+                       _ => panic!("Unexpected event"),
+               }
 
                assert_eq!(&tx_broadcaster.txn_broadcasted.lock().unwrap()[..], &[tx.clone()]);
 
-               let block = Block {
-                       header: BlockHeader { version: 0x20000000, prev_blockhash: BestBlock::from_network(network).block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: 42, bits: 42, nonce: 42 },
-                       txdata: vec![tx],
-               };
+               let block = create_dummy_block(BestBlock::from_network(network).block_hash(), 42, vec![tx]);
                Listen::block_connected(&node_a, &block, 1);
                Listen::block_connected(&node_b, &block, 1);
 
@@ -8964,40 +9982,33 @@ pub mod bench {
                        _ => panic!("Unexpected event"),
                }
 
-               let dummy_graph = NetworkGraph::new(network, &logger_a);
-
                let mut payment_count: u64 = 0;
                macro_rules! send_payment {
                        ($node_a: expr, $node_b: expr) => {
-                               let usable_channels = $node_a.list_usable_channels();
                                let payment_params = PaymentParameters::from_node_id($node_b.get_our_node_id(), TEST_FINAL_CLTV)
-                                       .with_features($node_b.invoice_features());
-                               let scorer = test_utils::TestScorer::new();
-                               let seed = [3u8; 32];
-                               let keys_manager = KeysManager::new(&seed, 42, 42);
-                               let random_seed_bytes = keys_manager.get_secure_random_bytes();
-                               let route = get_route(&$node_a.get_our_node_id(), &payment_params, &dummy_graph.read_only(),
-                                       Some(&usable_channels.iter().map(|r| r).collect::<Vec<_>>()), 10_000, TEST_FINAL_CLTV, &logger_a, &scorer, &random_seed_bytes).unwrap();
-
+                                       .with_bolt11_features($node_b.invoice_features()).unwrap();
                                let mut payment_preimage = PaymentPreimage([0; 32]);
                                payment_preimage.0[0..8].copy_from_slice(&payment_count.to_le_bytes());
                                payment_count += 1;
                                let payment_hash = PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner());
                                let payment_secret = $node_b.create_inbound_payment_for_hash(payment_hash, None, 7200, None).unwrap();
 
-                               $node_a.send_payment(&route, payment_hash, &Some(payment_secret), PaymentId(payment_hash.0)).unwrap();
+                               $node_a.send_payment(payment_hash, RecipientOnionFields::secret_only(payment_secret),
+                                       PaymentId(payment_hash.0), RouteParameters {
+                                               payment_params, final_value_msat: 10_000,
+                                       }, Retry::Attempts(0)).unwrap();
                                let payment_event = SendEvent::from_event($node_a.get_and_clear_pending_msg_events().pop().unwrap());
                                $node_b.handle_update_add_htlc(&$node_a.get_our_node_id(), &payment_event.msgs[0]);
                                $node_b.handle_commitment_signed(&$node_a.get_our_node_id(), &payment_event.commitment_msg);
-                               let (raa, cs) = do_get_revoke_commit_msgs!(NodeHolder { node: &$node_b }, &$node_a.get_our_node_id());
+                               let (raa, cs) = get_revoke_commit_msgs(&ANodeHolder { node: &$node_b }, &$node_a.get_our_node_id());
                                $node_a.handle_revoke_and_ack(&$node_b.get_our_node_id(), &raa);
                                $node_a.handle_commitment_signed(&$node_b.get_our_node_id(), &cs);
-                               $node_b.handle_revoke_and_ack(&$node_a.get_our_node_id(), &get_event_msg!(NodeHolder { node: &$node_a }, MessageSendEvent::SendRevokeAndACK, $node_b.get_our_node_id()));
+                               $node_b.handle_revoke_and_ack(&$node_a.get_our_node_id(), &get_event_msg!(ANodeHolder { node: &$node_a }, MessageSendEvent::SendRevokeAndACK, $node_b.get_our_node_id()));
 
-                               expect_pending_htlcs_forwardable!(NodeHolder { node: &$node_b });
-                               expect_payment_claimable!(NodeHolder { node: &$node_b }, payment_hash, payment_secret, 10_000);
+                               expect_pending_htlcs_forwardable!(ANodeHolder { node: &$node_b });
+                               expect_payment_claimable!(ANodeHolder { node: &$node_b }, payment_hash, payment_secret, 10_000);
                                $node_b.claim_funds(payment_preimage);
-                               expect_payment_claimed!(NodeHolder { node: &$node_b }, payment_hash, 10_000);
+                               expect_payment_claimed!(ANodeHolder { node: &$node_b }, payment_hash, 10_000);
 
                                match $node_b.get_and_clear_pending_msg_events().pop().unwrap() {
                                        MessageSendEvent::UpdateHTLCs { node_id, updates } => {
@@ -9008,18 +10019,18 @@ pub mod bench {
                                        _ => panic!("Failed to generate claim event"),
                                }
 
-                               let (raa, cs) = do_get_revoke_commit_msgs!(NodeHolder { node: &$node_a }, &$node_b.get_our_node_id());
+                               let (raa, cs) = get_revoke_commit_msgs(&ANodeHolder { node: &$node_a }, &$node_b.get_our_node_id());
                                $node_b.handle_revoke_and_ack(&$node_a.get_our_node_id(), &raa);
                                $node_b.handle_commitment_signed(&$node_a.get_our_node_id(), &cs);
-                               $node_a.handle_revoke_and_ack(&$node_b.get_our_node_id(), &get_event_msg!(NodeHolder { node: &$node_b }, MessageSendEvent::SendRevokeAndACK, $node_a.get_our_node_id()));
+                               $node_a.handle_revoke_and_ack(&$node_b.get_our_node_id(), &get_event_msg!(ANodeHolder { node: &$node_b }, MessageSendEvent::SendRevokeAndACK, $node_a.get_our_node_id()));
 
-                               expect_payment_sent!(NodeHolder { node: &$node_a }, payment_preimage);
+                               expect_payment_sent!(ANodeHolder { node: &$node_a }, payment_preimage);
                        }
                }
 
-               bench.iter(|| {
+               bench.bench_function(bench_name, |b| b.iter(|| {
                        send_payment!(node_a, node_b);
                        send_payment!(node_b, node_a);
-               });
+               }));
        }
 }