diff --git a/package.json b/package.json
index ed09248..cfacb14 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "mississippi",
-  "version": "3.0.0",
+  "version": "4.0.0",
   "description": "a collection of useful streams",
   "main": "index.js",
   "scripts": {