Welcome to Bun

Bun is an all-in-one JavaScript/TypeScript toolkit — runtime, package manager, bundler, and test runner in a single fast binary.

Bun is designed to be a drop-in replacement for Node.js. It starts 4x faster, installs packages up to 30x faster than npm, and includes everything you need to build, test, and ship JavaScript/TypeScript applications.

Runtime

Execute JS/TS files with near-zero overhead. TypeScript and JSX work out of the box.

Package Manager

Install packages up to 30x faster than npm, with workspaces and a global cache.

Bundler

Bundle TypeScript, JSX, CSS, and HTML for browsers and servers natively.

Test Runner

Jest-compatible test runner with snapshots, mocks, and DOM testing built in.

Get started in minutes

1. Install Bun

   Run the install script to download the single bun binary.

   curl -fsSL https://bun.sh/install | bash
   
2. Create a project

   Initialize a new project or use Bun in an existing Node.js project.

   mkdir my-app && cd my-app
   bun init
   
3. Run your code

   Run any TypeScript or JavaScript file directly — no compilation step needed.

   bun run index.ts
   
4. Install dependencies

   Install packages from npm faster than any other package manager.

   bun install
   

Explore by topic

HTTP Server

Build fast HTTP servers with Bun.serve() — supports WebSockets, TLS, and streaming.

SQLite

Query SQLite databases with Bun’s built-in, synchronous bun:sqlite driver.

Shell scripting

Use Bun.$ to write cross-platform shell scripts in TypeScript.

Node.js compatibility

Drop-in compatibility with Node.js APIs, globals, and npm packages.

Deployment guides

Docker

Containerize your Bun app with an optimized multi-stage Dockerfile.

Vercel

Deploy serverless Bun functions on Vercel Edge Runtime.

AWS Lambda

Run Bun on AWS Lambda with a custom runtime layer.

Railway

One-click deploy Bun applications to Railway.