Welcome to Bun

Bun is a fast, all-in-one JavaScript runtime and toolkit designed for speed and developer experience. Created by Jarred Sumner, Bun is built from scratch using Zig and JavaScriptCore (the engine that powers Safari).

What Makes Bun Special?

Bun is not just a runtime - it's a complete toolkit that includes:

• JavaScript/TypeScript Runtime: Execute JS and TS files directly
• Package Manager: A faster alternative to npm, yarn, and pnpm
• Bundler: Built-in bundling for production builds
• Test Runner: Native testing with Jest-compatible syntax
• Native APIs: Fast file I/O, HTTP server, SQLite, and more

Your First Bun Program

Let's start with a simple "Hello, Bun!" program. In this playground, you can write and execute Bun-compatible JavaScript:

Bun's Speed Advantage

Bun is designed for speed. It starts up faster than Node.js and executes JavaScript significantly quicker thanks to JavaScriptCore and optimizations in the runtime.

Exercise: Print Bun Info

Use the Bun global object to print information about the runtime:

What's Next?

In the following lessons, you'll learn:

1. Bun Basics - Core concepts and global APIs
2. TypeScript Support - Running TS without configuration
3. File I/O - Fast file operations
4. HTTP Servers - Building web servers with Bun.serve
5. Package Management - Using Bun as a package manager
6. Testing - Writing tests with Bun's test runner