diff --git a/package.json b/package.json
index f6e713dc4..6365ab7e0 100644
--- a/package.json
+++ b/package.json
@@ -11,6 +11,7 @@
     "check": "npm run test:build && _mocha --recursive specbuild --colors",
     "gendoc": "babel --no-babelrc -d .jsdocbuild src && jsdoc -r .jsdocbuild -P package.json -R README.md -d .jsdoc",
     "start": "babel -s -w -d lib src",
+    "clean": "rimraf lib dist",
     "build": "babel -s -d lib src && rimraf dist && mkdir dist && browserify -d browser-index.js | exorcist dist/browser-matrix.js.map > dist/browser-matrix.js && uglifyjs -c -m -o dist/browser-matrix.min.js --source-map dist/browser-matrix.min.js.map --in-source-map dist/browser-matrix.js.map dist/browser-matrix.js",
     "dist": "npm run build",
     "watch": "watchify -d browser-index.js -o 'exorcist dist/browser-matrix.js.map > dist/browser-matrix.js' -v",