-static mut REQUEST_BLOCK: Option<Box<Mutex<Arc<(u64, sha256d::Hash, Block)>>>> = None;
-static mut HIGHEST_HEADER: Option<Box<Mutex<(sha256d::Hash, u64)>>> = None;
-static mut HEADER_MAP: Option<Box<Mutex<HashMap<sha256d::Hash, u64>>>> = None;
-static mut HEIGHT_MAP: Option<Box<Mutex<HashMap<u64, sha256d::Hash>>>> = None;
+static mut REQUEST_BLOCK: Option<Box<Mutex<Arc<(u64, BlockHash, Block)>>>> = None;
+static mut HIGHEST_HEADER: Option<Box<Mutex<(BlockHash, u64)>>> = None;
+static mut HEADER_MAP: Option<Box<Mutex<HashMap<BlockHash, u64>>>> = None;
+static mut HEIGHT_MAP: Option<Box<Mutex<HashMap<u64, BlockHash>>>> = None;