Koa
https://gyazo.com/3be575d10680c5f3d5d2dc2d7b882c2f
Koa is a new web framework designed by the team behind Express, which aims to be a smaller, more expressive, and more robust foundation for web applications and APIs. Through leveraging generators Koa allows you to ditch callbacks and greatly increase error-handling. Koa does not bundle any middleware within core, and provides an elegant suite of methods that make writing servers fast and enjoyable.
目標
小さく
表現力がある
ロバスト(頑健)な基盤を実現する
を使っていて、コールバックがないので幸せ