diff --git a/keyserver/src/shared/state-sync/state-sync-specs.js b/keyserver/src/shared/state-sync/state-sync-specs.js
--- a/keyserver/src/shared/state-sync/state-sync-specs.js
+++ b/keyserver/src/shared/state-sync/state-sync-specs.js
@@ -6,11 +6,13 @@
 import { threadsStateSyncSpec } from './threads-state-sync-spec.js';
 import { usersStateSyncSpec } from './users-state-sync-spec.js';
 
-export const serverStateSyncSpecs: {
-  +[string]: ServerStateSyncSpec<*, *, *>,
-} = Object.freeze({
+export const serverStateSyncSpecs = Object.freeze({
   threads: threadsStateSyncSpec,
   entries: entriesStateSyncSpec,
   currentUser: currentUserStateSyncSpec,
   users: usersStateSyncSpec,
 });
+
+(serverStateSyncSpecs: {
+  +[string]: ServerStateSyncSpec<any, any, any>,
+});
diff --git a/lib/shared/state-sync/state-sync-specs.js b/lib/shared/state-sync/state-sync-specs.js
--- a/lib/shared/state-sync/state-sync-specs.js
+++ b/lib/shared/state-sync/state-sync-specs.js
@@ -6,11 +6,13 @@
 import { threadsStateSyncSpec } from './threads-state-sync-spec.js';
 import { usersStateSyncSpec } from './users-state-sync-spec.js';
 
-export const stateSyncSpecs: {
-  +[string]: StateSyncSpec<*>,
-} = Object.freeze({
+export const stateSyncSpecs = Object.freeze({
   threads: threadsStateSyncSpec,
   entries: entriesStateSyncSpec,
   currentUser: currentUserStateSyncSpec,
   users: usersStateSyncSpec,
 });
+
+(stateSyncSpecs: {
+  +[string]: StateSyncSpec<any>,
+});