diff --git a/package.json b/package.json
index 05b26d51..9d6978af 100644
--- a/package.json
+++ b/package.json
@@ -5,6 +5,7 @@
   "main": "./dist/y-websocket.cjs",
   "module": "./src/y-websocket.js",
   "types": "./dist/src/y-websocket.d.ts",
+  "type": "module",
   "sideEffects": false,
   "funding": {
     "type": "GitHub Sponsors ❤",