diff --git a/mdl/package.json b/mdl/package.json
index e3064d4..c08e0a9 100644
--- a/mdl/package.json
+++ b/mdl/package.json
@@ -12,7 +12,7 @@
     "babel-core": "6.26.3",
     "babel-preset-es2015": "6.24.1",
     "browser-sync": "2.24.4",
-    "chai": "3.5.0",
+    "chai": "4.3.9",
     "chai-jquery": "2.1.0",
     "del": "2.2.2",
     "drool": "0.4.0",