Bun Toolkit

Bun is a fast, all-in-one JavaScript runtime and toolkit.

Core Features

• Runtime: Fast JS/TS runtime, drop-in replacement for Node.js.
• Package Manager: bun install is significantly faster than npm or yarn.
• Test Runner: bun test provides a fast, Jest-compatible testing environment.
• Bundler: bun build for bundling JS/TS for the web or other runtimes.

Common Commands

bun init                        # Start a new project
bun install                     # Install dependencies
bun add <package>               # Add a package
bun run <script>                # Run a package.json script
bun <file.ts>                   # Run a TS/JS file directly
bun test                        # Run tests
bun build ./index.ts --outdir ./build # Build for production

Awareness & Best Practices

• TypeScript Support: Bun supports .ts and .tsx files out of the box. No separate compilation step needed.
• Environment Variables: Automatically loads .env files. Access via process.env or Bun.env.
• Fast I/O: Use Bun.file(path) and Bun.write(path, content) for high-performance file operations.
• HTTP Server: Use Bun.serve({ fetch(req) { ... } }) for an extremely fast built-in web server.
• SQLite: Built-in high-performance SQLite driver via import { Database } from "bun:sqlite".

When to use Bun Toolkit

• When the project has a bun.lockb file.
• When the user mentions "Bun".
• When performance is a priority for JS/TS tasks (installing, testing, running).
• For quick JS/TS scripts that need high performance.