diff --git a/package.json b/package.json
index afca0cc..39e232c 100644
--- a/package.json
+++ b/package.json
@@ -14,7 +14,7 @@
   "dependencies": {},
   "devDependencies": {
     "mocha": "*",
-    "chai": "*",
+    "chai": "3.5.0",
     "folio": "0.3.x"
   },
   "optionalDependencies": {},