unpkg

A fast, global content delivery network that mirrors every package published to npm, making any file from any npm package available within minutes of publication through a simple URL pattern combining package name, semantic version, and file path. The CDN is created by Michael Jackson, co-author of React Router and Remix, and runs entirely on the Cloudflare global edge network using Cloudflare Workers, enabling it to serve billions of requests per day from hundreds of locations worldwide with automatic scaling for traffic spikes. The URL format supports exact versions, npm distribution tags such as latest and next, semantic versioning ranges like caret and tilde, and directory browsing with a trailing slash that displays a file listing. A metadata API returns JSON with file paths, sizes, MIME types, and subresource integrity hashes for any package directory, enabling build tools and security scanners to verify file authenticity. The ESM subdomain transforms CommonJS modules into ES modules, compiles TypeScript and JSX on the fly, resolves dependency trees, and returns browser-ready modules with query parameters for target selection from es2015 through es2024, development mode, custom export conditions, dependency version overrides, package aliasing, tree-shaking, minification, sourcemaps, and web worker output. A runtime helper script scans HTML documents for inline scripts with type text/ts, text/jsx, or text/tsx, transforms them through the ESM compiler, and injects executable module scripts, enabling full TypeScript and JSX support in browser HTML without a build step. The service supports import maps for nobuild applications, CSS file serving with constructable stylesheet modules, and the full Node.js package exports specification including subpaths and conditional exports.