diff --git a/package.json b/package.json
index 5fbe2793c41..439c4d6fc86 100644
--- a/package.json
+++ b/package.json
@@ -27,7 +27,8 @@
     "eslint-fix": "eslint --ext js --ext ts --fix .",
     "lint": "npm run eslint && npm run tsc && npm run doc",
     "doc": "node utils/doclint/cli.js",
-    "tsc": "tsc --version && tsc -p . && cp src/protocol.d.ts lib/",
+    "clean-lib": "rm -rf lib",
+    "tsc": "npm run clean-lib && tsc --version && tsc -p . && cp src/protocol.d.ts lib/",
     "apply-next-version": "node utils/apply_next_version.js",
     "update-protocol-d-ts": "node utils/protocol-types-generator update",
     "compare-protocol-d-ts": "node utils/protocol-types-generator compare",