Zepto.js is a small JavaScript library for use in web browsers. The README describes it as a minimalist library for modern browsers with a largely jQuery-compatible API. jQuery is one of the older and most widely used JavaScript libraries; Zepto offers most of the same function names and behaviour so people who already know jQuery can use Zepto without relearning the basics. The point of Zepto is to be smaller and lighter than jQuery while doing many of the same things. The project's website at zeptojs.com hosts an extended introduction, downloads, and documentation. The README mentions that the library is released under the MIT license, and the author asks that anyone tempted to donate give to charity: water instead. Zepto is built from individual module files in the src directory, and you choose which modules to include when you build a custom bundle. The README lists each module in a table. The defaults are zepto (core methods), event (handlers via on and off), ajax (XMLHttpRequest and JSONP), form (form serialization and submission), and ie (Internet Explorer 10+ support). Optional modules add browser and operating system detection, animations through animate, show, hide, toggle, and fade methods, an arbitrary-object data store, a Deferred promises API with its callbacks dependency, jQuery-style CSS selectors, tap and swipe touch events, pinch gestures, chaining helpers like andSelf and end, an iOS image memory cleanup helper, and a compatibility module for iOS 3. Building requires Node.js. You run npm install, then npm run-script dist. A custom build is done by setting the MODULES environment variable to a space-separated list before running the script. The build produces dist/zepto.js and dist/zepto.min.js. If CoffeeScript is installed globally, the same can be done with the make script. Testing uses PhantomJS, a headless browser. npm test runs the automated tests; npm start launches a server you can open in real browsers on the local network at port 3000. Bug reports go to GitHub issues with browser and platform details, and documentation lives in a separate gh-pages branch that publishes to zeptojs.com.
Generated 2026-05-21 · Model: sonnet-4-6 · Verify against the repo before relying on details.