diff --git a/package.json b/package.json
index 1931a88..53f4d57 100644
--- a/package.json
+++ b/package.json
@@ -33,7 +33,7 @@
   },
   "homepage": "https://github.com/observing/emeeuw",
   "devDependencies": {
-    "assume": "~1.5.0",
+    "assume": "~2.0.1",
     "ejs": "~2.5.2",
     "istanbul": "~0.4.5",
     "mocha": "~3.1.2",