diff --git a/poulpy-core/src/conversion/glwe_to_lwe.rs b/poulpy-core/src/conversion/glwe_to_lwe.rs
index 276010d..072f3d5 100644
--- a/poulpy-core/src/conversion/glwe_to_lwe.rs
+++ b/poulpy-core/src/conversion/glwe_to_lwe.rs
@@ -112,14 +112,13 @@ impl<D: DataMut> LWE<D> {
         module.lwe_sample_extract(self, a);
     }
 
-    pub fn from_glwe<R, A, K, M, BE: Backend>(&self, module: &M, res: &mut R, a: &A, key: &K, scratch: &mut Scratch<BE>)
+    pub fn from_glwe<A, K, M, BE: Backend>(&mut self, module: &M, a: &A, key: &K, scratch: &mut Scratch<BE>)
     where
-        R: LWEToMut,
         A: GLWEToRef,
         K: GGLWEPreparedToRef<BE> + GGLWEInfos,
         M: LWEFromGLWE<BE>,
         Scratch<BE>: ScratchTakeCore<BE>,
     {
-        module.lwe_from_glwe(res, a, key, scratch);
+        module.lwe_from_glwe(self, a, key, scratch);
     }
 }
diff --git a/poulpy-core/src/encryption/glwe_to_lwe_ksk.rs b/poulpy-core/src/encryption/glwe_to_lwe_ksk.rs
index 71b96ff..28a9778 100644
--- a/poulpy-core/src/encryption/glwe_to_lwe_ksk.rs
+++ b/poulpy-core/src/encryption/glwe_to_lwe_ksk.rs
@@ -17,7 +17,7 @@ impl GLWEToLWESwitchingKey<Vec<u8>> {
     pub fn encrypt_sk_tmp_bytes<M, A, BE: Backend>(module: &M, infos: &A) -> usize
     where
         A: GGLWEInfos,
-        M: GLWEToLWESwitchingKeyEncrypt<BE>,
+        M: GLWEToLWESwitchingKeyEncryptSk<BE>,
     {
         module.glwe_to_lwe_switching_key_encrypt_sk_tmp_bytes(infos)
     }
@@ -33,7 +33,7 @@ impl<D: DataMut> GLWEToLWESwitchingKey<D> {
         source_xe: &mut Source,
         scratch: &mut Scratch<BE>,
     ) where
-        M: GLWEToLWESwitchingKeyEncrypt<BE>,
+        M: GLWEToLWESwitchingKeyEncryptSk<BE>,
         S1: LWESecretToRef,
         S2: GLWESecretToRef,
         Scratch<BE>: ScratchTakeCore<BE>,
@@ -42,7 +42,7 @@ impl<D: DataMut> GLWEToLWESwitchingKey<D> {
     }
 }
 
-pub trait GLWEToLWESwitchingKeyEncrypt<BE: Backend> {
+pub trait GLWEToLWESwitchingKeyEncryptSk<BE: Backend> {
     fn glwe_to_lwe_switching_key_encrypt_sk_tmp_bytes<A>(&self, infos: &A) -> usize
     where
         A: GGLWEInfos;
@@ -61,7 +61,7 @@ pub trait GLWEToLWESwitchingKeyEncrypt<BE: Backend> {
         R: GGLWEToMut;
 }
 
-impl<BE: Backend> GLWEToLWESwitchingKeyEncrypt<BE> for Module<BE>
+impl<BE: Backend> GLWEToLWESwitchingKeyEncryptSk<BE> for Module<BE>
 where
     Self: ModuleN
         + GGLWEEncryptSk<BE>
diff --git a/poulpy-core/src/encryption/lwe_to_glwe_ksk.rs b/poulpy-core/src/encryption/lwe_to_glwe_ksk.rs
index a9856cc..ddf6264 100644
--- a/poulpy-core/src/encryption/lwe_to_glwe_ksk.rs
+++ b/poulpy-core/src/encryption/lwe_to_glwe_ksk.rs
@@ -16,7 +16,7 @@ impl LWEToGLWESwitchingKey<Vec<u8>> {
     pub fn encrypt_sk_tmp_bytes<M, A, BE: Backend>(module: &M, infos: &A) -> usize
     where
         A: GGLWEInfos,
-        M: LWEToGLWESwitchingKeyEncrypt<BE>,
+        M: LWEToGLWESwitchingKeyEncryptSk<BE>,
     {
         module.lwe_to_glwe_switching_key_encrypt_sk_tmp_bytes(infos)
     }
@@ -34,14 +34,14 @@ impl<D: DataMut> LWEToGLWESwitchingKey<D> {
     ) where
         S1: LWESecretToRef,
         S2: GLWESecretPreparedToRef<BE>,
-        M: LWEToGLWESwitchingKeyEncrypt<BE>,
+        M: LWEToGLWESwitchingKeyEncryptSk<BE>,
         Scratch<BE>: ScratchTakeCore<BE>,
     {
         module.lwe_to_glwe_switching_key_encrypt_sk(self, sk_lwe, sk_glwe, source_xa, source_xe, scratch);
     }
 }
 
-pub trait LWEToGLWESwitchingKeyEncrypt<BE: Backend> {
+pub trait LWEToGLWESwitchingKeyEncryptSk<BE: Backend> {
     fn lwe_to_glwe_switching_key_encrypt_sk_tmp_bytes<A>(&self, infos: &A) -> usize
     where
         A: GGLWEInfos;
@@ -60,7 +60,7 @@ pub trait LWEToGLWESwitchingKeyEncrypt<BE: Backend> {
         R: GGLWEToMut;
 }
 
-impl<BE: Backend> LWEToGLWESwitchingKeyEncrypt<BE> for Module<BE>
+impl<BE: Backend> LWEToGLWESwitchingKeyEncryptSk<BE> for Module<BE>
 where
     Self: ModuleN
         + GGLWEEncryptSk<BE>
diff --git a/poulpy-core/src/layouts/glwe_to_lwe_ksk.rs b/poulpy-core/src/layouts/glwe_to_lwe_ksk.rs
index 1bb28ff..bc3ee4b 100644
--- a/poulpy-core/src/layouts/glwe_to_lwe_ksk.rs
+++ b/poulpy-core/src/layouts/glwe_to_lwe_ksk.rs
@@ -4,7 +4,7 @@ use poulpy_hal::{
 };
 
 use crate::layouts::{
-    Base2K, Degree, Dnum, Dsize, GGLWE, GGLWEInfos, GGLWEToMut, GGLWEToRef, GLWEInfos, GLWESwitchingKey,
+    Base2K, Degree, Dnum, Dsize, GGLWE, GGLWEInfos, GGLWEToMut, GGLWEToRef, GLWEInfos, GLWESwitchingKey, GLWESwitchingKeyDegrees,
     GLWESwitchingKeyDegreesMut, LWEInfos, Rank, TorusPrecision,
 };
 
@@ -217,3 +217,13 @@ impl<D: DataMut> GLWESwitchingKeyDegreesMut for GLWEToLWESwitchingKey<D> {
         &mut self.0.output_degree
     }
 }
+
+impl<D: DataRef> GLWESwitchingKeyDegrees for GLWEToLWESwitchingKey<D> {
+    fn input_degree(&self) -> &Degree {
+        &self.0.input_degree
+    }
+
+    fn output_degree(&self) -> &Degree {
+        &self.0.output_degree
+    }
+}
diff --git a/poulpy-core/src/layouts/lwe_to_glwe_ksk.rs b/poulpy-core/src/layouts/lwe_to_glwe_ksk.rs
index dbe95dd..caa676d 100644
--- a/poulpy-core/src/layouts/lwe_to_glwe_ksk.rs
+++ b/poulpy-core/src/layouts/lwe_to_glwe_ksk.rs
@@ -6,7 +6,7 @@ use poulpy_hal::{
 };
 
 use crate::layouts::{
-    Base2K, Degree, Dnum, Dsize, GGLWE, GGLWEInfos, GGLWEToMut, GGLWEToRef, GLWEInfos, GLWESwitchingKey,
+    Base2K, Degree, Dnum, Dsize, GGLWE, GGLWEInfos, GGLWEToMut, GGLWEToRef, GLWEInfos, GLWESwitchingKey, GLWESwitchingKeyDegrees,
     GLWESwitchingKeyDegreesMut, LWEInfos, Rank, TorusPrecision,
 };
 
@@ -217,3 +217,13 @@ impl<D: DataMut> GLWESwitchingKeyDegreesMut for LWEToGLWESwitchingKey<D> {
         &mut self.0.output_degree
     }
 }
+
+impl<D: DataRef> GLWESwitchingKeyDegrees for LWEToGLWESwitchingKey<D> {
+    fn input_degree(&self) -> &Degree {
+        &self.0.input_degree
+    }
+
+    fn output_degree(&self) -> &Degree {
+        &self.0.output_degree
+    }
+}
diff --git a/poulpy-core/src/layouts/prepared/glwe_to_lwe_ksk.rs b/poulpy-core/src/layouts/prepared/glwe_to_lwe_ksk.rs
index 716eeff..26d617f 100644
--- a/poulpy-core/src/layouts/prepared/glwe_to_lwe_ksk.rs
+++ b/poulpy-core/src/layouts/prepared/glwe_to_lwe_ksk.rs
@@ -206,3 +206,13 @@ impl<D: DataMut, B: Backend> GLWESwitchingKeyDegreesMut for GLWEToLWESwitchingKe
         &mut self.0.output_degree
     }
 }
+
+impl<D: DataRef, B: Backend> GLWESwitchingKeyDegrees for GLWEToLWESwitchingKeyPrepared<D, B> {
+    fn input_degree(&self) -> &Degree {
+        &self.0.input_degree
+    }
+
+    fn output_degree(&self) -> &Degree {
+        &self.0.output_degree
+    }
+}
diff --git a/poulpy-core/src/tests/mod.rs b/poulpy-core/src/tests/mod.rs
index f24ff84..595c480 100644
--- a/poulpy-core/src/tests/mod.rs
+++ b/poulpy-core/src/tests/mod.rs
@@ -59,8 +59,8 @@ ggsw_automorphism => crate::tests::test_suite::automorphism::test_ggsw_automorph
 ggsw_automorphism_inplace => crate::tests::test_suite::automorphism::test_ggsw_automorphism_inplace,
 // LWE
 lwe_keyswitch => crate::tests::test_suite::keyswitch::test_lwe_keyswitch,
-// glwe_to_lwe => crate::tests::test_suite::test_glwe_to_lwe,
-// lwe_to_glwe => crate::tests::test_suite::test_lwe_to_glwe,
+glwe_to_lwe => crate::tests::test_suite::test_glwe_to_lwe,
+lwe_to_glwe => crate::tests::test_suite::test_lwe_to_glwe,
 }
 );
 // #[cfg(test)]
diff --git a/poulpy-core/src/tests/test_suite/conversion.rs b/poulpy-core/src/tests/test_suite/conversion.rs
index 972e0c6..610b61e 100644
--- a/poulpy-core/src/tests/test_suite/conversion.rs
+++ b/poulpy-core/src/tests/test_suite/conversion.rs
@@ -1,68 +1,33 @@
 use poulpy_hal::{
-    api::{
-        ScratchOwnedAlloc, ScratchOwnedBorrow, SvpApplyDftToDftInplace, SvpPPolAlloc, SvpPPolBytesOf, SvpPrepare,
-        VecZnxAddInplace, VecZnxAddNormal, VecZnxAddScalarInplace, VecZnxAutomorphismInplace, VecZnxBigAddInplace,
-        VecZnxBigAddSmallInplace, VecZnxBigBytesOf, VecZnxBigNormalize, VecZnxBigNormalizeTmpBytes, VecZnxDftApply,
-        VecZnxDftBytesOf, VecZnxFillUniform, VecZnxIdftApplyConsume, VecZnxNormalize, VecZnxNormalizeInplace,
-        VecZnxNormalizeTmpBytes, VecZnxSub, VecZnxSubInplace, VecZnxSwitchRing, VmpApplyDftToDft, VmpApplyDftToDftAdd,
-        VmpApplyDftToDftTmpBytes, VmpPMatAlloc, VmpPrepare, ZnAddNormal, ZnFillUniform, ZnNormalizeInplace,
-    },
-    layouts::{Backend, Module, ScratchOwned, ZnxView},
-    oep::{
-        ScratchAvailableImpl, ScratchOwnedAllocImpl, ScratchOwnedBorrowImpl, TakeScalarZnxImpl, TakeSvpPPolImpl,
-        TakeVecZnxBigImpl, TakeVecZnxDftImpl, TakeVecZnxImpl,
-    },
+    api::{ScratchAvailable, ScratchOwnedAlloc, ScratchOwnedBorrow},
+    layouts::{Backend, Module, Scratch, ScratchOwned, ZnxView},
     source::Source,
 };
 
-use crate::layouts::{
-    Base2K, Degree, Dnum, GLWE, GLWELayout, GLWEPlaintext, GLWESecret, GLWEToLWEKeyLayout, GLWEToLWESwitchingKey, LWE,
-    LWECiphertextLayout, LWEPlaintext, LWESecret, LWEToGLWESwitchingKey, LWEToGLWESwitchingKeyLayout, Rank, TorusPrecision,
-    prepared::{GLWESecretPrepared, GLWEToLWESwitchingKeyPrepared, LWEToGLWESwitchingKeyPrepared, PrepareAlloc},
+use crate::{
+    GLWEDecrypt, GLWEEncryptSk, GLWEFromLWE, GLWEToLWESwitchingKeyEncryptSk, LWEDecrypt, LWEEncryptSk,
+    LWEToGLWESwitchingKeyEncryptSk, ScratchTakeCore,
+    layouts::{
+        Base2K, Degree, Dnum, GLWE, GLWELayout, GLWEPlaintext, GLWESecret, GLWESecretPrepare, GLWESecretPreparedAlloc,
+        GLWEToLWEKeyLayout, GLWEToLWESwitchingKey, GLWEToLWESwitchingKeyPrepare, GLWEToLWESwitchingKeyPreparedAlloc, LWE,
+        LWELayout, LWEPlaintext, LWESecret, LWEToGLWESwitchingKey, LWEToGLWESwitchingKeyLayout, LWEToGLWESwitchingKeyPrepare,
+        LWEToGLWESwitchingKeyPreparedAlloc, Rank, TorusPrecision,
+        prepared::{GLWESecretPrepared, GLWEToLWESwitchingKeyPrepared, LWEToGLWESwitchingKeyPrepared},
+    },
 };
 
-pub fn test_lwe_to_glwe<B>(module: &Module<B>)
+pub fn test_lwe_to_glwe<BE: Backend>(module: &Module<BE>)
 where
-    Module<B>: VecZnxDftBytesOf
-        + VecZnxBigNormalize<B>
-        + VecZnxDftApply<B>
-        + SvpApplyDftToDftInplace<B>
-        + VecZnxIdftApplyConsume<B>
-        + VecZnxFillUniform
-        + VecZnxSubInplace
-        + VecZnxAddInplace
-        + VecZnxNormalizeInplace<B>
-        + VecZnxAddNormal
-        + VecZnxNormalize<B>
-        + VecZnxSub
-        + SvpPrepare<B>
-        + SvpPPolBytesOf
-        + SvpPPolAlloc<B>
-        + VecZnxBigBytesOf
-        + VecZnxBigAddInplace<B>
-        + VecZnxBigAddSmallInplace<B>
-        + VecZnxNormalizeTmpBytes
-        + VecZnxAddScalarInplace
-        + VmpPMatAlloc<B>
-        + VmpPrepare<B>
-        + VmpApplyDftToDftTmpBytes
-        + VmpApplyDftToDft<B>
-        + VmpApplyDftToDftAdd<B>
-        + VecZnxBigNormalizeTmpBytes
-        + VecZnxSwitchRing
-        + VecZnxAutomorphismInplace<B>
-        + ZnNormalizeInplace<B>
-        + ZnFillUniform
-        + ZnAddNormal,
-    B: Backend
-        + TakeVecZnxDftImpl<B>
-        + TakeVecZnxBigImpl<B>
-        + TakeSvpPPolImpl<B>
-        + ScratchOwnedAllocImpl<B>
-        + ScratchOwnedBorrowImpl<B>
-        + ScratchAvailableImpl<B>
-        + TakeScalarZnxImpl<B>
-        + TakeVecZnxImpl<B>,
+    Module<BE>: GLWEFromLWE<BE>
+        + LWEToGLWESwitchingKeyEncryptSk<BE>
+        + GLWEDecrypt<BE>
+        + GLWESecretPrepare<BE>
+        + GLWESecretPreparedAlloc<BE>
+        + LWEEncryptSk<BE>
+        + LWEToGLWESwitchingKeyPreparedAlloc<BE>
+        + LWEToGLWESwitchingKeyPrepare<BE>,
+    ScratchOwned<BE>: ScratchOwnedAlloc<BE> + ScratchOwnedBorrow<BE>,
+    Scratch<BE>: ScratchAvailable + ScratchTakeCore<BE>,
 {
     let n_glwe: Degree = Degree(module.n() as u32);
     let n_lwe: Degree = Degree(22);
@@ -89,13 +54,13 @@ where
         rank,
     };
 
-    let lwe_infos: LWECiphertextLayout = LWECiphertextLayout {
+    let lwe_infos: LWELayout = LWELayout {
         n: n_lwe,
         base2k: Base2K(17),
         k: TorusPrecision(34),
     };
 
-    let mut scratch: ScratchOwned<B> = ScratchOwned::alloc(
+    let mut scratch: ScratchOwned<BE> = ScratchOwned::alloc(
         LWEToGLWESwitchingKey::encrypt_sk_tmp_bytes(module, &lwe_to_glwe_infos)
             | GLWE::from_lwe_tmp_bytes(module, &glwe_infos, &lwe_infos, &lwe_to_glwe_infos)
             | GLWE::decrypt_tmp_bytes(module, &glwe_infos),
@@ -104,7 +69,8 @@ where
     let mut sk_glwe: GLWESecret<Vec<u8>> = GLWESecret::alloc_from_infos(&glwe_infos);
     sk_glwe.fill_ternary_prob(0.5, &mut source_xs);
 
-    let sk_glwe_prepared: GLWESecretPrepared<Vec<u8>, B> = sk_glwe.prepare_alloc(module, scratch.borrow());
+    let mut sk_glwe_prepared: GLWESecretPrepared<Vec<u8>, BE> = GLWESecretPrepared::alloc_from_infos(module, &sk_glwe);
+    sk_glwe_prepared.prepare(module, &sk_glwe);
 
     let mut sk_lwe: LWESecret<Vec<u8>> = LWESecret::alloc(n_lwe);
     sk_lwe.fill_ternary_prob(0.5, &mut source_xs);
@@ -122,7 +88,7 @@ where
     ksk.encrypt_sk(
         module,
         &sk_lwe,
-        &sk_glwe,
+        &sk_glwe_prepared,
         &mut source_xa,
         &mut source_xe,
         scratch.borrow(),
@@ -130,7 +96,9 @@ where
 
     let mut glwe_ct: GLWE<Vec<u8>> = GLWE::alloc_from_infos(&glwe_infos);
 
-    let ksk_prepared: LWEToGLWESwitchingKeyPrepared<Vec<u8>, B> = ksk.prepare_alloc(module, scratch.borrow());
+    let mut ksk_prepared: LWEToGLWESwitchingKeyPrepared<Vec<u8>, BE> =
+        LWEToGLWESwitchingKeyPrepared::alloc_from_infos(module, &ksk);
+    ksk_prepared.prepare(module, &ksk, scratch.borrow());
 
     glwe_ct.from_lwe(module, &lwe_ct, &ksk_prepared, scratch.borrow());
 
@@ -140,46 +108,20 @@ where
     assert_eq!(glwe_pt.data.at(0, 0)[0], lwe_pt.data.at(0, 0)[0]);
 }
 
-pub fn test_glwe_to_lwe<B>(module: &Module<B>)
+pub fn test_glwe_to_lwe<BE: Backend>(module: &Module<BE>)
 where
-    Module<B>: VecZnxDftBytesOf
-        + VecZnxBigNormalize<B>
-        + VecZnxDftApply<B>
-        + SvpApplyDftToDftInplace<B>
-        + VecZnxIdftApplyConsume<B>
-        + VecZnxFillUniform
-        + VecZnxSubInplace
-        + VecZnxAddInplace
-        + VecZnxNormalizeInplace<B>
-        + VecZnxAddNormal
-        + VecZnxNormalize<B>
-        + VecZnxSub
-        + SvpPrepare<B>
-        + SvpPPolBytesOf
-        + SvpPPolAlloc<B>
-        + VecZnxBigBytesOf
-        + VecZnxBigAddInplace<B>
-        + VecZnxBigAddSmallInplace<B>
-        + VecZnxNormalizeTmpBytes
-        + VecZnxAddScalarInplace
-        + VmpPMatAlloc<B>
-        + VmpPrepare<B>
-        + VmpApplyDftToDftTmpBytes
-        + VmpApplyDftToDft<B>
-        + VmpApplyDftToDftAdd<B>
-        + VecZnxBigNormalizeTmpBytes
-        + VecZnxSwitchRing
-        + VecZnxAutomorphismInplace<B>
-        + ZnNormalizeInplace<B>,
-    B: Backend
-        + TakeVecZnxDftImpl<B>
-        + TakeVecZnxBigImpl<B>
-        + TakeSvpPPolImpl<B>
-        + ScratchOwnedAllocImpl<B>
-        + ScratchOwnedBorrowImpl<B>
-        + ScratchAvailableImpl<B>
-        + TakeScalarZnxImpl<B>
-        + TakeVecZnxImpl<B>,
+    Module<BE>: GLWEFromLWE<BE>
+        + GLWEToLWESwitchingKeyEncryptSk<BE>
+        + GLWEEncryptSk<BE>
+        + LWEDecrypt<BE>
+        + GLWEDecrypt<BE>
+        + GLWESecretPrepare<BE>
+        + GLWESecretPreparedAlloc<BE>
+        + GLWEToLWESwitchingKeyEncryptSk<BE>
+        + GLWEToLWESwitchingKeyPrepare<BE>
+        + GLWEToLWESwitchingKeyPreparedAlloc<BE>,
+    ScratchOwned<BE>: ScratchOwnedAlloc<BE> + ScratchOwnedBorrow<BE>,
+    Scratch<BE>: ScratchAvailable + ScratchTakeCore<BE>,
 {
     let n_glwe: Degree = Degree(module.n() as u32);
     let n_lwe: Degree = Degree(22);
@@ -202,7 +144,7 @@ where
         rank,
     };
 
-    let lwe_infos: LWECiphertextLayout = LWECiphertextLayout {
+    let lwe_infos: LWELayout = LWELayout {
         n: n_lwe,
         base2k: Base2K(17),
         k: TorusPrecision(34),
@@ -212,7 +154,7 @@ where
     let mut source_xa: Source = Source::new([0u8; 32]);
     let mut source_xe: Source = Source::new([0u8; 32]);
 
-    let mut scratch: ScratchOwned<B> = ScratchOwned::alloc(
+    let mut scratch: ScratchOwned<BE> = ScratchOwned::alloc(
         GLWEToLWESwitchingKey::encrypt_sk_tmp_bytes(module, &glwe_to_lwe_infos)
             | LWE::from_glwe_tmp_bytes(module, &lwe_infos, &glwe_infos, &glwe_to_lwe_infos)
             | GLWE::decrypt_tmp_bytes(module, &glwe_infos),
@@ -221,7 +163,8 @@ where
     let mut sk_glwe: GLWESecret<Vec<u8>> = GLWESecret::alloc_from_infos(&glwe_infos);
     sk_glwe.fill_ternary_prob(0.5, &mut source_xs);
 
-    let sk_glwe_prepared: GLWESecretPrepared<Vec<u8>, B> = sk_glwe.prepare_alloc(module, scratch.borrow());
+    let mut sk_glwe_prepared: GLWESecretPrepared<Vec<u8>, BE> = GLWESecretPrepared::alloc_from_infos(module, &sk_glwe);
+    sk_glwe_prepared.prepare(module, &sk_glwe);
 
     let mut sk_lwe: LWESecret<Vec<u8>> = LWESecret::alloc(n_lwe);
     sk_lwe.fill_ternary_prob(0.5, &mut source_xs);
@@ -230,7 +173,7 @@ where
     let mut glwe_pt: GLWEPlaintext<Vec<u8>> = GLWEPlaintext::alloc_from_infos(&glwe_infos);
     glwe_pt.encode_coeff_i64(data, k_lwe_pt, 0);
 
-    let mut glwe_ct = GLWE::alloc_from_infos(&glwe_infos);
+    let mut glwe_ct: GLWE<Vec<u8>> = GLWE::alloc_from_infos(&glwe_infos);
     glwe_ct.encrypt_sk(
         module,
         &glwe_pt,
@@ -240,7 +183,7 @@ where
         scratch.borrow(),
     );
 
-    let mut ksk: GLWEToLWESwitchingKey<Vec<u8>> = GLWEToLWESwitchingKey::alloc(&glwe_to_lwe_infos);
+    let mut ksk: GLWEToLWESwitchingKey<Vec<u8>> = GLWEToLWESwitchingKey::alloc_from_infos(&glwe_to_lwe_infos);
 
     ksk.encrypt_sk(
         module,
@@ -253,7 +196,9 @@ where
 
     let mut lwe_ct: LWE<Vec<u8>> = LWE::alloc_from_infos(&lwe_infos);
 
-    let ksk_prepared: GLWEToLWESwitchingKeyPrepared<Vec<u8>, B> = ksk.prepare_alloc(module, scratch.borrow());
+    let mut ksk_prepared: GLWEToLWESwitchingKeyPrepared<Vec<u8>, BE> =
+        GLWEToLWESwitchingKeyPrepared::alloc_from_infos(module, &ksk);
+    ksk_prepared.prepare(module, &ksk, scratch.borrow());
 
     lwe_ct.from_glwe(module, &glwe_ct, &ksk_prepared, scratch.borrow());
 
diff --git a/poulpy-core/src/tests/test_suite/mod.rs b/poulpy-core/src/tests/test_suite/mod.rs
index 11af37a..e3b8e28 100644
--- a/poulpy-core/src/tests/test_suite/mod.rs
+++ b/poulpy-core/src/tests/test_suite/mod.rs
@@ -3,10 +3,10 @@ pub mod encryption;
 pub mod external_product;
 pub mod keyswitch;
 
-// mod conversion;
+mod conversion;
 // mod packing;
 // mod trace;
 
-// pub use conversion::*;
+pub use conversion::*;
 // pub use packing::*;
 // pub use trace::*;