diff --git a/keyserver/src/updaters/thread-updaters.js b/keyserver/src/updaters/thread-updaters.js
--- a/keyserver/src/updaters/thread-updaters.js
+++ b/keyserver/src/updaters/thread-updaters.js
@@ -1,7 +1,5 @@
 // @flow
 
-import { getRustAPI } from 'rust-node-addon';
-
 import { specialRoles } from 'lib/permissions/special-roles.js';
 import { getRolePermissionBlobs } from 'lib/permissions/thread-permissions.js';
 import { filteredThreadIDs } from 'lib/selectors/calendar-filter-selectors.js';
@@ -69,9 +67,8 @@
   verifyUserOrCookieIDs,
 } from '../fetchers/user-fetchers.js';
 import type { Viewer } from '../session/viewer.js';
-import { verifyUserLoggedIn } from '../user/login.js';
 import { neynarClient } from '../utils/fc-cache.js';
-import { getContentSigningKey } from '../utils/olm-utils.js';
+import { findUserIdentities } from '../utils/identity-utils.js';
 import RelationshipChangeset from '../utils/relationship-changeset.js';
 
 type UpdateRoleOptions = {
@@ -937,18 +934,7 @@
   threadID: string,
   communityFarcasterChannelTag: string,
 ): Promise<string | null> {
-  const [rustAPI, identityInfo, deviceID] = await Promise.all([
-    getRustAPI(),
-    verifyUserLoggedIn(),
-    getContentSigningKey(),
-  ]);
-
-  const response = await rustAPI.findUserIdentities(
-    identityInfo.userId,
-    deviceID,
-    identityInfo.accessToken,
-    [viewer.userID],
-  );
+  const response = await findUserIdentities([viewer.userID]);
 
   const { farcasterID } = response.identities[viewer.userID];
 
diff --git a/keyserver/src/utils/identity-utils.js b/keyserver/src/utils/identity-utils.js
new file mode 100644
--- /dev/null
+++ b/keyserver/src/utils/identity-utils.js
@@ -0,0 +1,26 @@
+// @flow
+
+import { getRustAPI } from 'rust-node-addon';
+
+import type { UserIdentitiesResponse } from 'lib/types/identity-service-types.js';
+
+import { getContentSigningKey } from './olm-utils.js';
+import { verifyUserLoggedIn } from '../user/login.js';
+
+async function findUserIdentities(
+  userIDs: $ReadOnlyArray<string>,
+): Promise<UserIdentitiesResponse> {
+  const [rustAPI, identityInfo, deviceID] = await Promise.all([
+    getRustAPI(),
+    verifyUserLoggedIn(),
+    getContentSigningKey(),
+  ]);
+  return await rustAPI.findUserIdentities(
+    identityInfo.userId,
+    deviceID,
+    identityInfo.accessToken,
+    userIDs,
+  );
+}
+
+export { findUserIdentities };