Setup

Install Bun, pick an editor, run your first program.

Install Bun

macOS / Linux:

curl -fsSL https://bun.sh/install | bash

Windows:

powershell -c "irm bun.sh/install.ps1 | iex"

Verify:

bun --version

Editor

Use VS Code. Install the TypeScript extension (built-in) and the Bun extension for intellisense.

Other options: WebStorm, Zed, Neovim. All work. VS Code has the best TypeScript support.

Your first program

Create a file called index.ts:

console.log("Hello from Bun!")

Run it:

bun run index.ts

Output: Hello from Bun!

No build step. No package.json. No config. Write TypeScript, run it.

Create a project

For a real project, initialize properly:

mkdir my-app && cd my-app
bun init

This creates a package.json and tsconfig.json. The package.json tracks dependencies. The tsconfig.json configures TypeScript.

Install a dependency

bun add elysia

Bun installs packages into node_modules and updates package.json. Faster than npm, yarn, or pnpm.

Run scripts

In package.json:

{
  "scripts": {
    "dev": "bun run --watch index.ts"
  }
}

bun run dev

The --watch flag restarts the process when files change. No manual restart needed.

What you have now

• Bun runtime (runs TypeScript directly)
• A code editor with TypeScript support
• A project with package management
• Hot reload for development

That is the entire setup. No webpack, no babel, no compile step. Bun handles it all.