Instant builds by design. With Bun’s native speed, builds and rebuilds are extremely quick, even in monorepos. Faster feedback loops, higher productivity, calmer flow.

Create a TypeScript file:

// src/index.ts
export function greet(name: string): string {
  return `Hello, ${name}!`;
}

Build it instantly:

bunx bunup

Outputs to dist/ with ESM and .d.ts types.

Need CommonJS too?

bunx bunup --format esm,cjs

Want to generate and sync package exports automatically?

bunx bunup --exports

Spin up a modern, ready-to-publish TypeScript or React component library (or a basic starter) in ~10 seconds:

bunx @bunup/cli@latest create

See more in Scaffold with Bunup.

• ⚡ Instant builds — lightning-fast by default
• 🎨 CSS support out of the box — import CSS directly, with built-in CSS Modules support.
• 📝 TypeScript declarations — clean, accurate .d.ts files
• 🪓 Declaration splitting — smaller, cleaner type bundles
• 🔋 Batteries included — auto-exports, unused dependency detection, and more
• 🏗️ Workspace-ready — build multiple packages from one config and one command

For more, see the full documentation: https://bunup.dev

Check out the examples directory for example usage:

• Simple TypeScript library
• Workspace with multiple packages
• React component library styled with plain CSS
• React component library styled with CSS Modules
• React component library styled with Tailwind CSS

We welcome contributions! Please read the contributing guide.