React v0.13

Today, we’re happy to release React v0.13!

The most notable new feature is support for ES6 classes, which allows developers to have more flexibility when writing components. Our eventual goal is for ES6 classes to replace React.createClass completely, but until we have a replacement for current mixin use cases and support for class property initializers in the language, we don’t plan to deprecate React.createClass.

At EmberConf and ng-conf last week, we were excited to see that Ember and Angular have been working on speed improvements and now both have performance comparable to React. We’ve always thought that performance isn’t the most important reason to choose React, but we’re still planning more optimizations to make React even faster.

Our planned optimizations require that ReactElement objects are immutable, which has always been a best practice when writing idiomatic React code. In this release, we’ve added runtime warnings that fire when props are changed or added between the time an element is created and when it’s rendered. When migrating your code, you may want to use new React.cloneElement API (which is similar to React.addons.cloneWithProps but preserves key and ref and does not merge style or className automatically). For more information about our planned optimizations, see GitHub issues #3226, #3227, #3228.

The release is now available for download:

• React
  Dev build with warnings: https://fb.me/react-0.13.0.js
  Minified build for production: https://fb.me/react-0.13.0.min.js
• React with Add-Ons
  Dev build with warnings: https://fb.me/react-with-addons-0.13.0.js
  Minified build for production: https://fb.me/react-with-addons-0.13.0.min.js
• In-Browser JSX transformer
  https://fb.me/JSXTransformer-0.13.0.js

We’ve also published version 0.13.0 of the react and react-tools packages on npm and the react package on bower.

Changelog

React Core