diff --git a/VCL/VCL/api/keys/VCLKeyService.swift b/VCL/VCL/api/keys/VCLKeyService.swift
index b0b9e24..d9eeda0 100644
--- a/VCL/VCL/api/keys/VCLKeyService.swift
+++ b/VCL/VCL/api/keys/VCLKeyService.swift
@@ -18,11 +18,11 @@ public protocol VCLKeyService: Sendable {
     )
     func generateSecret(
         signatureAlgorithm: VCLSignatureAlgorithm,
-        completionBlock: @escaping @Sendable (VCLResult<VCCrypto.VCCryptoSecret>) -> Void
+        completionBlock: @escaping @Sendable (VCLResult<any VCCrypto.VCCryptoSecret>) -> Void
     )
     func retrieveSecretReference(
         keyId: String,
-        completionBlock: @escaping @Sendable (VCLResult<VCCrypto.VCCryptoSecret>) -> Void
+        completionBlock: @escaping @Sendable (VCLResult<any VCCrypto.VCCryptoSecret>) -> Void
     )
     func retrievePublicJwk(
         secret: VCCrypto.VCCryptoSecret,
diff --git a/VCL/VCL/impl/keys/VCLKeyServiceLocalImpl.swift b/VCL/VCL/impl/keys/VCLKeyServiceLocalImpl.swift
index 14ec792..9aad680 100644
--- a/VCL/VCL/impl/keys/VCLKeyServiceLocalImpl.swift
+++ b/VCL/VCL/impl/keys/VCLKeyServiceLocalImpl.swift
@@ -52,7 +52,8 @@ final class VCLKeyServiceLocalImpl: VCLKeyService {
     }
     
     func generateSecret(
-        completionBlock: @escaping @Sendable (VCLResult<VCCryptoSecret>) -> Void
+        signatureAlgorithm: VCLSignatureAlgorithm = VCLSignatureAlgorithm.SECP256k1, // ignored
+        completionBlock: @escaping @Sendable (VCLResult<VCCrypto.VCCryptoSecret>) -> Void
     ) {
         do {
             completionBlock(.success(try keyManagementOperations.generateKey()))
diff --git a/VCL/VCLTests/infrastructure/resources/valid/VCLKeyServiceMock.swift b/VCL/VCLTests/infrastructure/resources/valid/VCLKeyServiceMock.swift
index 1b9791e..e758923 100644
--- a/VCL/VCLTests/infrastructure/resources/valid/VCLKeyServiceMock.swift
+++ b/VCL/VCLTests/infrastructure/resources/valid/VCLKeyServiceMock.swift
@@ -12,7 +12,7 @@ import VCToken
 import VCCrypto
 @testable import VCL
 
-class VCLKeyServiceMock: VCLKeyService {
+final class VCLKeyServiceMock: VCLKeyService {
     func generateDidJwk(
         didJwkDescriptor: VCLDidJwkDescriptor,
         completionBlock: @escaping @Sendable (VCLResult<VCLDidJwk>) -> Void