diff --git a/package.json b/package.json
index 56bf1f1..faeffb8 100644
--- a/package.json
+++ b/package.json
@@ -26,7 +26,7 @@
     "madge": "^0.5.4"
   },
   "devDependencies": {
-    "chai": "^3.5.0",
+    "chai": "^4.2.0",
     "eslint": "^2.11.1",
     "eslint-config-airbnb": "^9.0.1",
     "eslint-plugin-import": "^1.8.1",