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[![Express Logo](https://i.cloudup.com/zfY6lL7eFa-3000x3000.png)](http://expressjs.com/)

  Fast, unopinionated, minimalist web framework for [Node.js](http://nodejs.org).

  [![NPM Version][npm-version-image]][npm-url]
  [![NPM Install Size][npm-install-size-image]][npm-install-size-url]
  [![NPM Downloads][npm-downloads-image]][npm-downloads-url]

```js
const express = require('express')
const app = express()

app.get('/', function (req, res) {
  res.send('Hello World')
})

app.listen(3000)
```

## Installation

This is a [Node.js](https://nodejs.org/en/) module available through the
[npm registry](https://www.npmjs.com/).

Before installing, [download and install Node.js](https://nodejs.org/en/download/).
Node.js 0.10 or higher is required.

If this is a brand new project, make sure to create a `package.json` first with
the [`npm init` command](https://docs.npmjs.com/creating-a-package-json-file).

Installation is done using the
[`npm install` command](https://docs.npmjs.com/getting-started/installing-npm-packages-locally):

```console
$ npm install express
```

Follow [our installing guide](http://expressjs.com/en/starter/installing.html)
for more information.

## Features

  * Robust routing
  * Focus on high performance
  * Super-high test coverage
  * HTTP helpers (redirection, caching, etc)
  * View system supporting 14+ template engines
  * Content negotiation
  * Executable for generating applications quickly

## Docs & Community

  * [Website and Documentation](http://expressjs.com/) - [[website repo](https://github.com/expressjs/expressjs.com)]
  * [#express](https://web.libera.chat/#express) on [Libera Chat](https://libera.chat) IRC
  * [GitHub Organization](https://github.com/expressjs) for Official Middleware & Modules
  * Visit the [Wiki](https://github.com/expressjs/express/wiki)
  * [Google Group](https://groups.google.com/group/express-js) for discussion
  * [Gitter](https://gitter.im/expressjs/express) for support and discussion

**PROTIP** Be sure to read [Migrating from 3.x to 4.x](https://github.com/expressjs/express/wiki/Migrating-from-3.x-to-4.x) as well as [New features in 4.x](https://github.com/expressjs/express/wiki/New-features-in-4.x).

## Quick Start

  The quickest way to get started with express is to utilize the executable [`express(1)`](https://github.com/expressjs/generator) to generate an application as shown below:

  Install the executable. The executable's major version will match Express's:

```console
$ npm install -g express-generator@4
```

  Create the app:

```console
$ express /tmp/foo && cd /tmp/foo
```

  Install dependencies:

```console
$ npm install
```

  Start the server:

```console
$ npm start
```

  View the website at: http://localhost:3000

## Philosophy

  The Express philosophy is to provide small, robust tooling for HTTP servers, making
  it a great solution for single page applications, websites, hybrids, or public
  HTTP APIs.

  Express does not force you to use any specific ORM or template engine. With support for over
  14 template engines via [Consolidate.js](https://github.com/tj/consolidate.js),
  you can quickly craft your perfect framework.

## Examples

  To view the examples, clone the Express repo and install the dependencies:

```console
$ git clone https://github.com/expressjs/express.git --depth 1
$ cd express
$ npm install
```

  Then run whichever example you want:

```console
$ node examples/content-negotiation
```

## Contributing

  [![Linux Build][github-actions-ci-image]][github-actions-ci-url]
  [![Windows Build][appveyor-image]][appveyor-url]
  [![Test Coverage][coveralls-image]][coveralls-url]

The Express.js project welcomes all constructive contributions. Contributions take many forms,
from code for bug fixes and enhancements, to additions and fixes to documentation, additional
tests, triaging incoming pull requests and issues, and more!

See the [Contributing Guide](Contributing.md) for more technical details on contributing.

### Security Issues

If you discover a security vulnerability in Express, please see [Security Policies and Procedures](Security.md).

### Running Tests

To run the test suite, first install the dependencies, then run `npm test`:

```console
$ npm install
$ npm test
```

## People

The original author of Express is [TJ Holowaychuk](https://github.com/tj)

The current lead maintainer is [Douglas Christopher Wilson](https://github.com/dougwilson)

[List of all contributors](https://github.com/expressjs/express/graphs/contributors)

## License

  [MIT](LICENSE)

[appveyor-image]: https://badgen.net/appveyor/ci/dougwilson/express/master?label=windows
[appveyor-url]: https://ci.appveyor.com/project/dougwilson/express
[coveralls-image]: https://badgen.net/coveralls/c/github/expressjs/express/master
[coveralls-url]: https://coveralls.io/r/expressjs/express?branch=master
[github-actions-ci-image]: https://badgen.net/github/checks/expressjs/express/master?label=linux
[github-actions-ci-url]: https://github.com/expressjs/express/actions/workflows/ci.yml
[npm-downloads-image]: https://badgen.net/npm/dm/express
[npm-downloads-url]: https://npmcharts.com/compare/express?minimal=true
[npm-install-size-image]: https://badgen.net/packagephobia/install/express
[npm-install-size-url]: https://packagephobia.com/result?p=express
[npm-url]: https://npmjs.org/package/express
[npm-version-image]: https://badgen.net/npm/v/express