dep-locker

Pin dependency versions to their lock file resolutions for supply-chain security.

Why This Exists

Software supply-chain attacks are no longer rare — they happen almost weekly. Attackers compromise maintainer accounts or take over abandoned packages, then push new versions containing malware. Because most projects use range constraints like ^1.2.0 or ~1.2.0, a simple npm install or composer update can silently pull in a compromised release.

The two most effective defenses are straightforward:

1. Pin exact versions — so your project only installs the versions you've vetted, not whatever is newest
2. Disable post-install scripts — since postinstall is the primary vector attackers use to execute malicious code

This tool automates both. It reads your lock file to find the versions you're actually running, pins your manifest to those exact versions, and configures .npmrc to enforce these practices going forward.

Usage

Run in your project root:

npx @kirschbaum-development/dep-locker

The tool will:

1. Detect which package managers are in use (npm, yarn, bun, composer)
2. Configure .npmrc with security best practices (save-exact=true, ignore-scripts=true)
3. Pin all dependencies to the exact versions resolved in your lock file
4. Re-run install to sync the lock file with the updated constraints

Supported Package Managers

Manager	Manifest	Lock File
npm	package.json	package-lock.json
yarn	package.json	yarn.lock
bun	package.json	bun.lock
composer	composer.json	composer.lock

What It Does

Given a package.json with:

{
  "dependencies": {
    "lodash": "^4.17.0",
    "express": "~4.18.0"
  }
}

And a lock file that resolved lodash to 4.17.21 and express to 4.18.3, the tool will update package.json to:

{
  "dependencies": {
    "lodash": "4.17.21",
    "express": "4.18.3"
  }
}

Features

• Interactive prompts — confirm before making changes, choose which dependency types to pin
• No downgrades — pins to the version currently in your lock file
• .npmrc configuration — optionally adds save-exact=true and ignore-scripts=true
• Skips non-pinnable deps — git refs, file links, workspace protocols, and branch aliases are left untouched
• Preserves formatting — detects and maintains your manifest file's indentation style

Options

The tool runs interactively. You'll be prompted to:

• Select .npmrc options (both checked by default):
  • save-exact=true — ensures future installs use exact versions
  • ignore-scripts=true — blocks post-install scripts (primary malware vector)
• Choose dependency types to pin:
  • dependencies, devDependencies, optionalDependencies (checked by default)
  • peerDependencies (unchecked by default — typically left as ranges)
  • For composer: require and require-dev (both checked by default)

Requirements

• Node.js >= 18

License

MIT