diff --git a/src/oauth-client-temp/client/crypto-implementation.ts b/src/oauth-client-temp/client/crypto-implementation.ts
index e69de29bb2..bf3b340011 100644
--- a/src/oauth-client-temp/client/crypto-implementation.ts
+++ b/src/oauth-client-temp/client/crypto-implementation.ts
@@ -0,0 +1,11 @@
+import {Key} from '../jwk'
+
+export type DigestAlgorithm = {
+  name: 'sha256' | 'sha384' | 'sha512'
+}
+
+export type {Key}
+
+export interface CryptoImplementation {
+  createKey(algs: )
+}