Babel browser transform based on https://github.com/facebook/react/blob/master/vendor/browser-transforms.js.
It's pretty much the JSX transformer by Facebook but running your code through Babel, giving you
ES6 and ES7 (as well as JSX) on-the-fly compilation for free :).
Will pick up any script tag with the types text/babel, text/es6, text/es7 and text/jsx.
It exports BabelTransform.transform and BabelTransform.exec.
A note on the license. Had to use BSD because that's what React uses.