Package Manager Security

This skill helps you harden npm, pnpm, and bun against supply chain attacks. It provides configuration guides, best practices, and troubleshooting for all three package managers.

How to use this skill

1. Identify which package manager(s) the user's query is about (npm, pnpm, bun, or multiple)
2. If they ask about npm → read references/npm.md
3. If they ask about pnpm → read references/pnpm.md
4. If they ask about bun → read references/bun.md
5. If they ask about multiple or general concepts (lockfiles, CI/CD, version pinning) → read all relevant files
6. Answer concisely and directly. Provide configuration snippets and commands the user can copy/paste.

Common concepts (apply to all three)

These security practices apply regardless of package manager. Mention them when relevant.

Lockfile enforcement

• Always commit the lockfile: package-lock.json (npm), pnpm-lock.yaml (pnpm), bun.lock (bun)
• In CI/CD, use the frozen-lockfile equivalent:
• npm: npm ci
• pnpm: pnpm install --frozen-lockfile
• bun: bun install --frozen-lockfile
• Review lockfile changes in PRs — unexpected additions can indicate compromised deps

Version pinning

• Prefer exact versions ("axios": "1.12.0") over ranges ("axios": "^1.12.0")
• Tilde ranges ("axios": "~1.12.0") are safer than caret ranges for production
• Never use "*" or "latest" in production

Supply chain monitoring

• npm audit signatures — verify package provenance
• Integrate SCA (Software Composition Analysis) tools for vulnerability scanning
• Block known C2 domains at the firewall/DNS level

Audit existing setup

Run python scripts/audit.py to check global security settings (npmrc, pnpm config, bunfig).

Run python scripts/audit-project.py from your project root to check project-level settings (package.json: overrides, engines, packageManager, pnpm config).

Run python scripts/scan-exotic.py to scan lockfiles for dependencies from exotic sources (git repos, tarballs, local paths). Use --ci to fail in CI if any exotic deps found.

Output format

When providing configuration:

1. Show the exact file content (with file path comment)
2. Explain what each setting does
3. Provide the command to apply it
4. If troubleshooting, explain the root cause

References

• references/npm.md — npm-specific security configuration
• references/pnpm.md — pnpm-specific security configuration
• references/bun.md — bun-specific security configuration
• references/cross-cutting.md — Registries, overrides, engines, SBOM, lockfile review, git deps
• scripts/audit.py — Audit script that checks all global security settings
• scripts/audit-project.py — Project-level audit (package.json checks)
• scripts/scan-exotic.py — Lockfile scanner for exotic dependency sources