Fast, unopinionated, minimalist web framework for Node.js

$ npm install express --save

const express = require('express')
const app = express()
const port = 3000

app.get('/', (req, res) => {
  res.send('Hello World!')
})

app.listen(port, () => {
  console.log(`Example app listening on port ${port}`)
})

Express@5.1.0: LTSタイムラインでnpmのデフォルトになりました

Express 5.1.0 が npm のデフォルトとなり、v4 および v5 リリースラインの公式 LTS スケジュールが導入されます。詳細については、最新のブログをご覧ください。

Web Applications

Express is a minimal and flexible Node.js web application framework that provides a robust set of features for web and mobile applications.

APIs

With a myriad of HTTP utility methods and middleware at your disposal, creating a robust API is quick and easy.

Performance

Express provides a thin layer of fundamental web application features, without obscuring Node.js features that you know and love.

ミドルウェア

Express is a lightweight and flexible routing framework with minimal core features meant to be augmented through the use of Express middleware modules.