diff --git a/modules/openapi/src/commonMain/kotlin/com/sphereon/oid/fed/openapi/openapi.yaml b/modules/openapi/src/commonMain/kotlin/com/sphereon/oid/fed/openapi/openapi.yaml
index c8ba18d..e910b38 100644
--- a/modules/openapi/src/commonMain/kotlin/com/sphereon/oid/fed/openapi/openapi.yaml
+++ b/modules/openapi/src/commonMain/kotlin/com/sphereon/oid/fed/openapi/openapi.yaml
@@ -1530,7 +1530,6 @@ components:
           type: string
           description: The key ID.
           example: 12345
-          nullable: true
         x:
           type: string
           description: The X coordinate for EC keys (optional).
diff --git a/modules/openid-federation-client/src/commonMain/kotlin/com/sphereon/oid/fed/client/fetch/Fetch.kt b/modules/openid-federation-client/src/commonMain/kotlin/com/sphereon/oid/fed/client/fetch/Fetch.kt
index 57fddaa..ddc7e1d 100644
--- a/modules/openid-federation-client/src/commonMain/kotlin/com/sphereon/oid/fed/client/fetch/Fetch.kt
+++ b/modules/openid-federation-client/src/commonMain/kotlin/com/sphereon/oid/fed/client/fetch/Fetch.kt
@@ -1,8 +1,5 @@
 package com.sphereon.oid.fed.client.fetch
 
-import kotlin.js.JsExport
-
-@JsExport.Ignore
 interface IFetchService {
     suspend fun fetchStatement(
         endpoint: String
diff --git a/modules/openid-federation-client/src/jsMain/kotlin/com/sphereon/oid/fed/client/Client.js.kt b/modules/openid-federation-client/src/jsMain/kotlin/com/sphereon/oid/fed/client/Client.js.kt
index 41e7307..4e34f02 100644
--- a/modules/openid-federation-client/src/jsMain/kotlin/com/sphereon/oid/fed/client/Client.js.kt
+++ b/modules/openid-federation-client/src/jsMain/kotlin/com/sphereon/oid/fed/client/Client.js.kt
@@ -1,23 +1,42 @@
 import com.sphereon.oid.fed.client.crypto.CryptoServiceAdapter
 import com.sphereon.oid.fed.client.crypto.ICryptoService
-import com.sphereon.oid.fed.client.crypto.ICryptoServiceJS
 import com.sphereon.oid.fed.client.crypto.cryptoService
 import com.sphereon.oid.fed.client.fetch.FetchServiceAdapter
 import com.sphereon.oid.fed.client.fetch.IFetchService
-import com.sphereon.oid.fed.client.fetch.IFetchServiceJS
 import com.sphereon.oid.fed.client.fetch.fetchService
 import com.sphereon.oid.fed.client.trustchain.TrustChain
-import kotlinx.coroutines.*
+import com.sphereon.oid.fed.openapi.models.Jwk
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.SupervisorJob
+import kotlinx.coroutines.promise
 import kotlin.js.Promise
 
+@JsExport
+@JsName("ICryptoService")
+external interface ICryptoServiceJS {
+    fun verify(
+        jwt: String,
+        key: Jwk
+    ): Promise<Boolean>
+}
+
+@JsExport
+@JsName("IFetchService")
+external interface IFetchServiceJS {
+    fun fetchStatement(endpoint: String): Promise<String>
+}
+
 @JsExport
 @JsName("FederationClient")
 class FederationClientJS(
     fetchServiceCallback: IFetchServiceJS?,
     cryptoServiceCallback: ICryptoServiceJS?,
 ) {
-    private val fetchService: IFetchService = if (fetchServiceCallback != null) FetchServiceAdapter(fetchServiceCallback) else fetchService()
-    private val cryptoService: ICryptoService = if (cryptoServiceCallback != null) CryptoServiceAdapter(cryptoServiceCallback) else cryptoService()
+    private val fetchService: IFetchService =
+        if (fetchServiceCallback != null) FetchServiceAdapter(fetchServiceCallback) else fetchService()
+    private val cryptoService: ICryptoService =
+        if (cryptoServiceCallback != null) CryptoServiceAdapter(cryptoServiceCallback) else cryptoService()
 
     private val trustChainService: TrustChain = TrustChain(fetchService, cryptoService)
 
@@ -27,11 +46,11 @@ class FederationClientJS(
     fun resolveTrustChainJS(
         entityIdentifier: String,
         trustAnchors: Array<String>,
-        timeout: Int = 10
+        maxDepth: Int = 10
     ): Promise<Array<String>?> {
         return scope.promise {
             try {
-                trustChainService.resolve(entityIdentifier, trustAnchors, timeout)?.toTypedArray()
+                trustChainService.resolve(entityIdentifier, trustAnchors, maxDepth)?.toTypedArray()
             } catch (e: Exception) {
                 throw RuntimeException("Failed to resolve trust chain: ${e.message}", e)
             }
diff --git a/modules/openid-federation-client/src/jsMain/kotlin/com/sphereon/oid/fed/client/crypto/Crypto.js.kt b/modules/openid-federation-client/src/jsMain/kotlin/com/sphereon/oid/fed/client/crypto/Crypto.js.kt
index ea73ef0..c0c1f1c 100644
--- a/modules/openid-federation-client/src/jsMain/kotlin/com/sphereon/oid/fed/client/crypto/Crypto.js.kt
+++ b/modules/openid-federation-client/src/jsMain/kotlin/com/sphereon/oid/fed/client/crypto/Crypto.js.kt
@@ -1,5 +1,6 @@
 package com.sphereon.oid.fed.client.crypto
 
+import ICryptoServiceJS
 import com.sphereon.oid.fed.client.mapper.decodeJWTComponents
 import com.sphereon.oid.fed.openapi.models.Jwk
 import kotlinx.coroutines.await
@@ -14,23 +15,14 @@ external object Jose {
     fun jwtVerify(jwt: String, key: Any, options: dynamic = definedExternally): Promise<dynamic>
 }
 
-@JsExport
-@JsName("CryptoService")
-external interface ICryptoServiceJS {
-    fun verify(
-        jwt: String,
-        key: String
-    ): Promise<Boolean>
-}
-
 class CryptoServiceAdapter(private val jsCryptoService: ICryptoServiceJS) : ICryptoService {
     override suspend fun verify(jwt: String, key: Jwk): Boolean {
-        return jsCryptoService.verify(jwt, Json.encodeToString(Jwk.serializer(), key)).await()
+        return jsCryptoService.verify(jwt, key).await()
     }
 }
 
 object CryptoServiceJS : ICryptoServiceJS {
-    override fun verify(jwt: String, key: String): Promise<Boolean> {
+    override fun verify(jwt: String, key: Jwk): Promise<Boolean> {
         return Promise { resolve, reject ->
             try {
                 val decodedJwt = decodeJWTComponents(jwt)
@@ -58,7 +50,7 @@ object CryptoServiceJS : ICryptoServiceJS {
 actual fun cryptoService(): ICryptoService {
     return object : ICryptoService {
         override suspend fun verify(jwt: String, key: Jwk): Boolean {
-            return CryptoServiceJS.verify(jwt, Json.encodeToString(key)).await()
+            return CryptoServiceJS.verify(jwt, key).await()
         }
     }
 }
diff --git a/modules/openid-federation-client/src/jsMain/kotlin/com/sphereon/oid/fed/client/fetch/Fetch.js.kt b/modules/openid-federation-client/src/jsMain/kotlin/com/sphereon/oid/fed/client/fetch/Fetch.js.kt
index d3c48f3..b1cf1ea 100644
--- a/modules/openid-federation-client/src/jsMain/kotlin/com/sphereon/oid/fed/client/fetch/Fetch.js.kt
+++ b/modules/openid-federation-client/src/jsMain/kotlin/com/sphereon/oid/fed/client/fetch/Fetch.js.kt
@@ -1,18 +1,12 @@
 package com.sphereon.oid.fed.client.fetch
 
+import IFetchServiceJS
 import io.ktor.client.*
 import io.ktor.client.call.*
 import io.ktor.client.engine.js.*
 import io.ktor.client.request.*
 import io.ktor.http.*
 import kotlinx.coroutines.await
-import kotlin.js.Promise
-
-@JsExport
-@JsName("IFetchService")
-interface IFetchServiceJS {
-    fun fetchStatement(endpoint: String): Promise<String>
-}
 
 class FetchServiceAdapter(private val jsFetchService: IFetchServiceJS) : IFetchService {
     override suspend fun fetchStatement(endpoint: String): String {