Node.Js: Learning Koa.Js By Building REST APIs
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 Koaallows 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.
Does Koa replace Express?
Koa is more like Connect, but a lot of the Express goodies were moved to the middleware level in Koa to help form a stronger foundation. Koa makes middleware more enjoyable and less error-prone to write, for the entire stack, not just the end application code.