Air.js is an ES6 benchmark. It tries to faithfully use new features like arrow functions, classes, for-of, and Map/Set, among others. Air.js doesn't avoid any features out of fear that they might be slow, in the hope that we might learn how to make those features fast by looking at how Air.js and other benchmarks use them. This documents the motivation, design, and license of Air.js. To run Air.js