diff --git a/package.json b/package.json
index 97768bd..f302da6 100644
--- a/package.json
+++ b/package.json
@@ -33,6 +33,7 @@
     "audio-format": "^2.3.2",
     "is-audio-buffer": "^1.0.11",
     "is-buffer": "^1.1.5",
-    "object-assign": "^4.1.1"
+    "object-assign": "^4.1.1",
+    "assert": "^2.0.0",
   }
 }