diff --git a/js/package.json b/js/package.json
index 18843cd8..5bcc8a07 100644
--- a/js/package.json
+++ b/js/package.json
@@ -26,6 +26,7 @@
     "fs-extra": "^6.0.1",
     "glob": "^7.1.2",
     "handlebars": "^4.0.11",
+    "mkdirp": "^0.5.1",
     "rimraf": "^2.6.2",
     "webpack": "^4.1.1",
     "webpack-cli": "^2.0.10"