diff --git a/package.json b/package.json
index e1477d8..ff686ee 100755
--- a/package.json
+++ b/package.json
@@ -211,6 +211,7 @@
     "src"
   ],
   "bin": "./script/cli.js",
+  "sideEffects": false,
   "scripts": {
     "build": "./script/build-dist.sh && ./script/build-esm.js",
     "build+test": "npm run build && npm run test",