npm v12 disables preinstall/install/postinstall scripts by default. The dangerous part: npm ci doesn't fail — it just skips the script. Projects relying on install scripts (native compilation, prebuilt binary downloads — sharp, bcrypt, canvas, sqlite3...) can build green in CI and only fail later, at runtime or in production. Paste your package.json below to see which of your dependencies are known to rely on an install script and deserve manual verification before you migrate.
Runs entirely in your browser · nothing is uploaded · results are deterministic (same input, same output, every time) · npm v12 changelog ↗
The analysis runs entirely in your browser. Your package.json content is never uploaded or sent anywhere. This page does send anonymous, content-free usage pings (e.g. "analysis completed") to help us learn whether this tool is useful — never your file, never anything you typed.
This page is a free, one-off manual check. A CI integration that re-checks every dependency change automatically — instead of you remembering to paste your package.json here — is a hypothesis, not built yet.
This page checks against a curated list of commonly-affected packages, entirely client-side, for free, no limit.
The Pro tier is a hypothesis, not yet built. If you'd want it, the free tool above is the whole product for now.
npm v12 shipped July 8, 2026. It's a real, current, silent-failure risk — not a hypothetical one. Existing guides explain the change; this page instead tells you, specifically, whether your project is affected.
It scans your dependencies, devDependencies, and optionalDependencies against a curated list of packages known to rely on install scripts (native compilation, prebuilt binary downloads, etc.) and flags each match with the reason it's at risk.
It cannot see your transitive dependencies (packages required by your packages), and a package absent from the list is not proof it's safe — only that we don't have evidence either way. Always verify with npm ci on a real npm v12 environment before shipping.