Koa is a minimal web framework for node.js.

Only methods that are common to nearly all HTTP servers are integrated directly into Koa’s small ~570 SLOC codebase. This includes things like content negotiation, normalization of node inconsistencies, redirection, and a few others.

Koa is not bundled with any middleware.

This is quite unlike express.

There is an ecosystem of npm modules around koa that implement all sorts of useful middleware.

Koa leverages async functions, allowing us to avoid callback hell and implement error handling with greater ease.

Koa is awesome [citation needed].

Useful modules

Minimal Koa app

import Koa from "koa";
import Router from "koa-router";

const app = new Koa();
const router = new Router();

router.get("/", async (ctx) => {
    ctx.body = "response";


app.listen(process.env.PORT || 3000);