http://koajs.com/ http://koajs.com/ In Koa, handlers don't respond to the request. Instead, they update a representation of the response and return a promise.

http://koajs.com/ http://koajs.com/ In Koa, handlers don't respond to the request. Instead, they update a representation of the response and return a promise. The response bubbles up to the top-level where the `res.send()` is done. This way you have real middleware. You can post-process the response or do something else entirely after the downstream has run. const middleware = async (ctx, next) => { console.log('request going down') await next() console.log('request coming up') }