diff --git a/package.json b/package.json
index dc7d37e..4f507e0 100644
--- a/package.json
+++ b/package.json
@@ -47,7 +47,7 @@
   },
   "devDependencies": {
     "argh": "0.1.x",
-    "assume": "~1.5.0",
+    "assume": "~2.0.0",
     "async-each": "~1.0.1",
     "browserify": "^16.0.0",
     "http-proxy": "~1.16.2",