When it runs
On every pre-bash hook firing for an install command (npm install, pip install; alternative installers like poetry, uv, and pipenv are not recognised yet). The hook reads the lockfile diff, computes the set of newly-resolved packages, and calls the dep-check skill before the install proceeds.
What it checks
Approved-list match: was this package (and version range) approved at design review? If yes, fast-path allow.
Provenance: who published this version, when, from what build pipeline? A maintainer change in the last 30 days raises the bar.
Reputation: package age, download history, repo legitimacy. New, low-download packages get extra scrutiny. OpenSSF Scorecard scores arrive in v1.
Supply-chain integrity: cross-checked against npm registry, PyPI, and the OSV vulnerability database; NVD arrives in v1. Active CVE → hard block.
npm registry package metadata, publish history, maintainer set PyPI / pip API same for Python packages OSV.dev open-source vulnerability database OpenSSF Scorecards composite supply-chain hygiene score · v1 NVD national vulnerability database · v1 # all queried server-side; your laptop sees only the verdict
Ecosystems today
Today: npm and pip. yarn, pnpm, poetry, cargo, go modules, and bundler are on the roadmap; the underlying engine is ecosystem-agnostic, so adding one is configuration plus a lockfile parser.
↳ npm install axios
flowrail-dep-check · deny
✗ axios@1.14.1 4 supply-chain signals
- maintainer changed 6 days ago
- publishing pipeline differs from prior versions
- active CVE-2026-XXXXX (severity: high)
- approved range was ^1.13.0
suggested fix pin axios@1.13.4 (last clean version)