diff --git a/test-serializer/tsconfig.json b/test-serializer/tsconfig.json
index 01226b65..70aa257f 100644
--- a/test-serializer/tsconfig.json
+++ b/test-serializer/tsconfig.json
@@ -9,7 +9,7 @@
     ],
     "types": [
       "node",
-      "es6-shim"
+      "core-js"
     ]
   }
 }
\ No newline at end of file