diff --git a/bitcoin/Cargo.toml b/bitcoin/Cargo.toml
index 714471dc..5d1fd3c3 100644
--- a/bitcoin/Cargo.toml
+++ b/bitcoin/Cargo.toml
@@ -28,7 +28,7 @@ bitcoinconsensus-std = ["bitcoinconsensus/std", "std"]
 # Instead no-std enables additional features required for this crate to be usable without std.
 # As a result, both can be enabled without conflict.
 std = ["secp256k1/std", "bitcoin_hashes/std", "bech32/std", "bitcoin-internals/std"]
-no-std = ["core2/alloc", "bitcoin_hashes/alloc", "bitcoin_hashes/core2", "secp256k1/alloc"]
+no-std = ["core2", "bitcoin_hashes/alloc", "bitcoin_hashes/core2", "secp256k1/alloc"]
 
 [package.metadata.docs.rs]
 features = [ "std", "secp-recovery", "base64", "rand", "serde", "bitcoinconsensus" ]
@@ -39,10 +39,10 @@ bitcoin-internals = { path = "../internals" }
 bech32 = { version = "0.9.0", default-features = false }
 bitcoin_hashes = { version = "0.11.0", default-features = false }
 secp256k1 = { version = "0.25.0", default-features = false, features = ["bitcoin_hashes"] }
-core2 = { version = "0.3.0", optional = true, default-features = false }
 
 base64 = { version = "0.13.0", optional = true }
 bitcoinconsensus = { version = "0.20.2-0.5.0", optional = true, default-features = false }
+core2 = { version = "0.3.0", default-features = false, features = ["alloc"], optional = true }
 # Do NOT use this as a feature! Use the `serde` feature instead.
 actual-serde = { package = "serde", version = "1.0.103", default-features = false, features = [ "derive", "alloc" ], optional = true }