We built an API with which you can now host your own Hacker News of X! Obviously, we're still missing the sort and decay algorithm, as well as comments, but since you reached this far, it should be an easy exercise for you.

The purpose of this chapter was really to give you a taste of the neat features of Koa.js, and demonstrate the use of the generator function pattern, which will be available in ECMAScript 6. If you like being on the bleeding edge, and enjoy the generator syntax, it is definitely a good alternative to Express.js.