diff --git a/Cargo.lock b/Cargo.lock
index 936ab2f..2100195 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -192,7 +192,7 @@ version = "0.5.0-rc.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bd4ef774202f1749465fc7cf88d70fc30620e8cacd5429268f4bff7d003bd976"
 dependencies = [
- "crypto-common",
+ "crypto-common 0.2.0-rc.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "inout",
 ]
 
@@ -357,6 +357,15 @@ dependencies = [
  "hybrid-array",
 ]
 
+[[package]]
+name = "crypto-common"
+version = "0.2.0-rc.4"
+source = "git+https://github.com/RustCrypto/traits#0ba3c983654a31077b0f1da3a3233e58f4a2230a"
+dependencies = [
+ "hybrid-array",
+ "rand_core",
+]
+
 [[package]]
 name = "cstr_core"
 version = "0.2.6"
@@ -437,7 +446,7 @@ checksum = "dac89f8a64533a9b0eaa73a68e424db0fb1fd6271c74cc0125336a05f090568d"
 dependencies = [
  "block-buffer",
  "const-oid",
- "crypto-common",
+ "crypto-common 0.2.0-rc.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "subtle",
 ]
 
@@ -791,9 +800,9 @@ dependencies = [
 [[package]]
 name = "kem"
 version = "0.4.0-pre.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c1ec5336e2804a5746a2cf0575537afae902c0a29e82c542918b4c5adf392456"
+source = "git+https://github.com/RustCrypto/traits#0ba3c983654a31077b0f1da3a3233e58f4a2230a"
 dependencies = [
+ "crypto-common 0.2.0-rc.4 (git+https://github.com/RustCrypto/traits)",
  "rand_core",
  "zeroize",
 ]
diff --git a/Cargo.toml b/Cargo.toml
index c01e6f8..3fbdc81 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -12,3 +12,5 @@ debug = true
 
 [patch.crates-io]
 ml-kem = { path = "./ml-kem" }
+
+kem = { git = "https://github.com/RustCrypto/traits" }
diff --git a/ml-kem/src/kem.rs b/ml-kem/src/kem.rs
index 5386467..f63f3e2 100644
--- a/ml-kem/src/kem.rs
+++ b/ml-kem/src/kem.rs
@@ -1,6 +1,6 @@
 use core::convert::Infallible;
 use core::marker::PhantomData;
-use hybrid_array::typenum::U32;
+use hybrid_array::typenum::{U32, U64};
 use rand_core::{CryptoRng, TryCryptoRng};
 use subtle::{ConditionallySelectable, ConstantTimeEq};
 
@@ -98,6 +98,23 @@ where
     }
 }
 
+impl<P> ::kem::KeySizeUser for DecapsulationKey<P>
+where
+    P: KemParams,
+{
+    type KeySize = U64;
+}
+
+impl<P> ::kem::KeyInit for DecapsulationKey<P>
+where
+    P: KemParams,
+{
+    #[inline]
+    fn new(seed: &Seed) -> Self {
+        Self::from_seed(*seed)
+    }
+}
+
 impl<P> ::kem::Decapsulate<EncodedCiphertext<P>, SharedKey> for DecapsulationKey<P>
 where
     P: KemParams,
diff --git a/x-wing/src/lib.rs b/x-wing/src/lib.rs
index 5735ed4..8a6e85a 100644
--- a/x-wing/src/lib.rs
+++ b/x-wing/src/lib.rs
@@ -29,7 +29,7 @@
 pub use kem::{self, Decapsulate, Encapsulate};
 
 use core::convert::Infallible;
-use ml_kem::array::ArrayN;
+use ml_kem::array::{ArrayN, typenum::consts::U32};
 use ml_kem::{B32, EncodedSizeUser, KemCore, MlKem768, MlKem768Params};
 use rand_core::{CryptoRng, TryCryptoRng};
 #[cfg(feature = "os_rng")]
@@ -145,6 +145,16 @@ impl Decapsulate<Ciphertext, SharedSecret> for DecapsulationKey {
     }
 }
 
+impl ::kem::KeySizeUser for DecapsulationKey {
+    type KeySize = U32;
+}
+
+impl ::kem::KeyInit for DecapsulationKey {
+    fn new(key: &ArrayN<u8, 32>) -> Self {
+        Self { sk: key.0 }
+    }
+}
+
 impl DecapsulationKey {
     /// Generate a new `DecapsulationKey` using `OsRng`.
     #[cfg(feature = "os_rng")]