diff --git a/package.json b/package.json
index 542c14a..5ed8596 100644
--- a/package.json
+++ b/package.json
@@ -23,6 +23,7 @@
     "walk-up-path": "^3.0.1"
   },
   "scripts": {
+    "preversion": "npm test",
     "postversion": "npm publish",
     "prepublishOnly": "git push origin --follow-tags",
     "prepare": "tsc -p .tshy/esm.json && bash scripts/fixup.sh",