diff --git a/backend/src/lib/datastore.ts b/backend/src/lib/datastore.ts
index 7e9dd82..45a8f7e 100644
--- a/backend/src/lib/datastore.ts
+++ b/backend/src/lib/datastore.ts
@@ -26,7 +26,8 @@ let _provider: DatastoreProvider | null = null;
 export function initDatastore(): DatastoreProvider {
   if (_provider) return _provider;
 
-  const dbProvider = (process.env.DB_PROVIDER || 'cosmos').toLowerCase();
+  const isTest = process.env.NODE_ENV === 'test';
+  const dbProvider = (process.env.DB_PROVIDER || (isTest ? 'memory' : 'cosmos')).toLowerCase();
 
   if (dbProvider === 'memory') {
     _provider = new MemoryDatastoreProvider();
@@ -43,6 +44,7 @@ export function initDatastore(): DatastoreProvider {
  */
 export function setProvider(provider: DatastoreProvider): void {
   _provider = provider;
+  setDatastore(provider);
 }
 
 /**