Browserify

Browserify is a development tool that lets developers use Node.js-style CommonJS modules in web browsers by bundling up dependencies into a single JavaScript file. It analyzes the dependency graph starting from an entry point, resolves require() calls using the CommonJS module resolution rules, and outputs a bundle that includes a small module loader suitable for the browser. The resulting bundle can be loaded in a typical HTML page and provides a working require function and module.exports/exports as seen in Node.js.

Browserify was created by James Halliday (a.k.a. substack) and became one of the early popular approaches to bringing npm packages to the browser without rewriting code for AMD or ES modules. It is built on Node.js and runs as a command-line tool, but also provides a programmatic API for integration. A typical workflow uses the command line to generate a bundle, for example: browserify entry.js -o bundle.js. Developers can extend browserify with transforms to transpile code (for example, Babelify), inline text, or shim environment globals. For incremental rebuilding, the watchify plugin can be used to update bundles when source files change.

In practice, Browserify served as a bridge between Node-style modules and browser environments before native ES module support and modern bundlers gained ground. It remains in use in some projects that rely on existing npm ecosystems or prefer a simple bundling approach. Alternatives include Webpack, Rollup, and Parcel, which offer broader features for modern web applications.

See also: CommonJS, Module bundler, Node.js, Web development tools.