You can use Fly with ES6 too if you would like. Another difference is, Fly itself is written in ES6, in a very functional style, with a small dependency footpri

You can use Fly with ES6 too if you would like. Another difference is, Fly itself is written in ES6, in a very functional style, with a small dependency footprint and a tiny code base. Its implementation is based in promise sequences and co-routines (the same library that powers Koa.js) giving you co-routine async flow (async/await style) support out of the box.