A web application for comparing different versions of npm packages and WordPress plugins. View the diff between any two versions with syntax highlighting, word-level diff detection, and a file tree navigator.

Live: diff.almeidx.dev

• Compare npm packages and WordPress plugins
• Unified and split diff views
• Syntax highlighting for common languages
• Word-level diff highlighting within changed lines
• File tree filtering and keyboard navigation
• Dark/light theme support
• Mobile responsive

Running locally removes the size and memory limits imposed by Cloudflare Workers, allowing you to diff larger packages.

• Node.js 24+
• pnpm

# Clone the repository
git clone https://github.com/almeidx/diff.git
cd diff

# Install dependencies
pnpm install --frozen-lockfile

# Start the development server
pnpm dev

The app will be available at http://localhost:5173.

• pnpm dev - Uses Vite's dev server. Faster hot reload, but no Cloudflare Cache API (caching is skipped).
• pnpm preview - Uses Wrangler to simulate the Cloudflare Workers environment locally, including the Cache API.

• SvelteKit - Full-stack framework
• Cloudflare Workers - Edge runtime
• fflate - Fast zip/gzip decompression
• diff-match-patch - Diff algorithm
• Prism.js - Syntax highlighting

The hosted version has the following limits due to Cloudflare Workers constraints:

• Maximum compressed archive size: 50MB
• Maximum decompressed size: ~128MB
• Maximum files per package: 5,000
• Maximum file size: 1MB per file

For larger packages, run locally where these limits don't apply.

• The diff view renders files incrementally to keep initial page load responsive on large diffs.
• npm .tgz archives are extracted in a streaming path to lower peak memory pressure.
• Zip extraction still requires full archive download due format constraints.

Rate limiting supports two modes:

• KV-backed distributed rate limiting when RATE_LIMIT_KV is bound in Cloudflare.
• In-memory fallback when running locally without KV.

Add this binding in your Cloudflare config if you want shared limits across instances:

{
	"kv_namespaces": [
		{
			"binding": "RATE_LIMIT_KV",
			"id": "your-kv-namespace-id",
		},
	],
}

• Package too large errors: Run locally (pnpm dev) to bypass Cloudflare Worker runtime limits.
• Corrupted or truncated tar archive: The upstream package tarball is malformed or incomplete; retry and confirm the package version exists.
• No versions returned for package/plugin: Check package name/slug spelling and that your network can reach npm/WordPress APIs.
• UI slows down on huge diffs: Use file-tree filtering to narrow the diff and load relevant files first.

See CONTRIBUTING.md for development workflow and standards. Operational deployment and incident guidance is in docs/OPERATIONS.md.

GNU GPLv3