diff --git a/examples/mongodb-crud/backend/src/models/Global.ts b/examples/mongodb-crud/backend/src/models/Global.ts
index 7e31c83..ff5f945 100644
--- a/examples/mongodb-crud/backend/src/models/Global.ts
+++ b/examples/mongodb-crud/backend/src/models/Global.ts
@@ -8,25 +8,10 @@ export class Global {
     static db: Db;
 
     static async init(logger?: Logger) {
-        this.db = await this._getMongoDb(BackConfig.mongoDb, logger);
-    }
-
-    private static _getMongoDb(uri: string, logger?: Logger): Promise<Db> {
-        logger?.log(`Start connecting db...(${uri})`)
-        let promise = new Promise<Db>((rs, rj) => {
-            MongoClient.connect(uri, {
-                useUnifiedTopology: true,
-            }, (err, client) => {
-                if (err) {
-                    logger?.error('× Failed connected db.', err)
-                    rj(err);
-                } else {
-                    logger?.log(`√ Connect db succ. (${uri})`)
-                    rs(client.db());
-                }
-            })
-        })
-        return promise;
+        logger?.log(`Start connecting db...`)
+        const client = await new MongoClient(BackConfig.mongoDb).connect();
+        logger?.log(`Db connected successfully...`)
+        this.db = client.db();
     }
 
     static collection<T extends keyof DbCollectionType>(col: T): Collection<DbCollectionType[T]> {
diff --git a/examples/mongodb-crud/backend/test/api/post.test.ts b/examples/mongodb-crud/backend/test/api/post.test.ts
index f443a39..4c939c8 100644
--- a/examples/mongodb-crud/backend/test/api/post.test.ts
+++ b/examples/mongodb-crud/backend/test/api/post.test.ts
@@ -1,3 +1,4 @@
+import assert from 'assert';
 import { HttpClient } from 'tsrpc';
 import { Post } from '../../src/shared/protocols/models/Post';
 import { serviceProto } from '../../src/shared/protocols/serviceProto';