diff --git a/package.json b/package.json
index a078b01..ab6f8a0 100644
--- a/package.json
+++ b/package.json
@@ -33,7 +33,7 @@
   "homepage": "https://github.com/libp2p/interface-stream-muxer",
   "dependencies": {
     "async": "^2.1.5",
-    "chai": "^3.5.0",
+    "chai": "^4.0.1",
     "chai-checkmark": "^1.0.1",
     "detect-node": "^2.0.3",
     "libp2p-tcp": "~0.9.3",