diff --git a/package.json b/package.json
index 1e39a54..5a4b73e 100644
--- a/package.json
+++ b/package.json
@@ -23,6 +23,7 @@
     "lint:ci": "eslint index.js",
     "prepush": "pnpm run lint && pnpm test",
     "postpublish": "git tag $npm_package_version && git push origin --tags && pnpm run chore",
+    "preinstall": "npx only-allow pnpm",
     "report:coverage": "nyc report --reporter=lcov > coverage.lcov && codecov",
     "test": "nyc mocha test.js --timeout 10s --coverage"
   },