diff --git a/src/rln.ts b/src/rln.ts
index 8bb4efa..3f66ce0 100644
--- a/src/rln.ts
+++ b/src/rln.ts
@@ -308,7 +308,7 @@ export class RLNInstance {
 
   public async registerMembership(
     options: RegisterMembershipOptions
-  ): Promise<undefined | KeystoreEntity> {
+  ): Promise<undefined | DecryptedCredentials> {
     if (!this.contract) {
       throw Error("RLN Contract is not initialized.");
     }
diff --git a/src/rln_contract.ts b/src/rln_contract.ts
index 6fc82e5..5570d77 100644
--- a/src/rln_contract.ts
+++ b/src/rln_contract.ts
@@ -3,7 +3,7 @@ import { ethers } from "ethers";
 
 import { zeroPadLE } from "./byte_utils.js";
 import { RLN_REGISTRY_ABI, RLN_STORAGE_ABI } from "./constants.js";
-import type { KeystoreEntity } from "./keystore/index.js";
+import type { DecryptedCredentials } from "./keystore/index.js";
 import { type IdentityCredential, RLNInstance } from "./rln.js";
 import { MerkleRootTracker } from "./root_tracker.js";
 
@@ -210,7 +210,7 @@ export class RLNContract {
 
   public async registerWithIdentity(
     identity: IdentityCredential
-  ): Promise<KeystoreEntity | undefined> {
+  ): Promise<DecryptedCredentials | undefined> {
     if (this.storageIndex === undefined) {
       throw Error(
         "Cannot register credential, no storage contract index found."