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expressjs/express

🔥 Hot★ 69,036JavaScriptAudience · developerComplexity · 2/5ActiveLicenseSetup · easy

TLDR

Minimal web framework for Node.js that handles HTTP requests, routes, and responses without forcing a rigid structure on your app.

Mindmap

mindmap
  root((Express))
    What it does
      Handle HTTP requests
      Define routes
      Send responses
      Middleware support
    Key features
      Unopinionated design
      Template engines
      Built-in helpers
      Composable
    Use cases
      REST APIs
      Web backends
      Single-page apps
      Internal services
    Tech stack
      Node.js
      JavaScript
      npm

Things people build with this

USE CASE 1

Build a REST API that serves JSON data to a mobile or web app.

USE CASE 2

Create a web server that renders HTML pages using a template engine like EJS or Pug.

USE CASE 3

Set up a backend for a single-page application that handles authentication and database queries.

USE CASE 4

Build internal microservices or small web services without heavy framework overhead.

Tech stack

JavaScriptNode.jsnpm

Getting it running

Difficulty · easy Time to first run · 5min
Use freely for any purpose, including commercial use, as long as you keep the copyright notice.

In plain English

Express is a minimal and flexible web framework for Node.js, the JavaScript runtime that lets you run JavaScript on a server rather than just in a browser. It is one of the most widely used web frameworks in the JavaScript ecosystem, providing the essential building blocks for creating web servers and HTTP APIs without imposing a rigid structure on how you organize your application. What it does is give you a straightforward way to handle HTTP requests and send back responses. You define routes, essentially rules that say "when someone visits this URL with this method (GET, POST, etc.), run this function." Express takes care of parsing the incoming request, matching it to the right route, and giving you simple tools to send back text, HTML, JSON, or whatever the client needs. It also supports middleware, which are small functions that run before your route handlers, used for tasks like logging, authentication, or parsing request bodies. The framework is intentionally kept small and unopinionated, meaning it does not dictate which database you use, which template engine renders your HTML, or how you structure your files. This makes it highly composable, you add exactly the pieces you need, and nothing more. It supports over 14 template engines for server-side HTML rendering and includes built-in helpers for things like redirects and caching. You would reach for Express whenever you need to build a web server, a REST API, or a backend for a web or mobile application using JavaScript. It is especially popular for single-page application backends, internal APIs, and small-to-medium web services. The project runs on Node.js 18 or higher and is installed via npm.

Copy-paste prompts

Prompt 1
Show me how to create a basic Express server that listens on port 3000 and responds to GET requests.
Prompt 2
How do I set up middleware in Express to log incoming requests and parse JSON request bodies?
Prompt 3
Walk me through creating a REST API with Express that handles GET, POST, and DELETE routes for a todo list.
Prompt 4
How do I use Express to serve static files like CSS and JavaScript from a public folder?
Prompt 5
Show me how to connect Express to a template engine like EJS to render dynamic HTML pages.
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Generated 2026-05-18 · Model: sonnet-4-6 · Verify against the repo before relying on details.