-bitcoin_hashes = { version = "0.10", default-features = false }
-hashbrown = { version = "0.11", optional = true }
-core2 = { version = "0.3.0", default-features = false, optional = true }
+bitcoin_hashes = { version = "0.11", default-features = false }
+hashbrown = { version = "0.8", optional = true }