diff --git a/package.json b/package.json
index c8c1d188ba..eb23e34214 100644
--- a/package.json
+++ b/package.json
@@ -12,6 +12,7 @@
   "dependencies": {
     "assert": "^1.4.1",
     "awesome-phonenumber": "^1.0.13",
+    "babel-plugin-transform-es2015-block-scoping": "6.15.0",
     "browserify-zlib": "^0.1.4",
     "chance": "1.0.4",
     "console-browserify": "^1.1.0",