bunup

Bunup is the high-performance build tool for TypeScript and JavaScript libraries, with first-class support for libraries built with Bun. It delivers lightning-fast builds — up to ~50× faster than Tsup.

Bundler	Format	Build Time	Build Time (with dts)
bunup	esm, cjs	3.14ms ⚡️	19.86ms ⚡️
tsdown	esm, cjs	5.60ms	56.87ms
unbuild	esm, cjs	41.19ms	321.09ms
tsup	esm, cjs	62.59ms	937.64ms

Lower is better. Benchmarks run on identical code and output formats.

Want proof? Clone the repo, run pnpm benchmark, and check benchmarks/results.md for yourself!

Key Features

• ⚡️ Ultra Fast Builds: Lightning-fast performance powered by Bun's native bundler and Oxc.

• 🔥 Bytecode Generation: Faster startups by compiling to Bun bytecode—perfect for CLIs.

• 📦 Workspace Support: Build multiple packages with defineWorkspace() in one config file and command.

• 🔄 Tsup Familiarity: Familiar tsup-like CLI and config.

• 🎯 Bun Targeting: Optimize for Bun runtime with --target bun for native features.

🚀 Quick Start

Installations

# Using Bun
bun add bunup -d

# Using pnpm
pnpm add bunup -D

# Using npm
npm i bunup -D

# Using Yarn
yarn add bunup --dev

Basic Usage

Create a simple TypeScript file:

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

Bundle it with bunup:

bunup src/index.ts

This will create a bundled output in the dist directory.

Using with package.json

Add a build script to your package.json:

{
  "name": "my-package",
  "scripts": {
    "build": "bunup src/index.ts --format esm,cjs --dts"
  }
}

Then run:

npm run build

⚙️ Configuration File

Create a bunup.config.ts file for more control:

import { defineConfig } from "bunup";

export default defineConfig({
  entry: ["src/index.ts"],
  outDir: "dist",
  format: ["esm", "cjs"],
  dts: true,
  minify: true,
});

📚 Documentation

For complete documentation, visit the full documentation.

⚡️ Create TypeScript Libraries Faster

Quickly scaffold modern TypeScript library in 10 seconds. Powered by bunup.

# Using bun
bunx create-bunup@latest

# Using npm
npx create-bunup@latest

# Using pnpm
pnpx create-bunup@latest

Check out our TypeScript Library Starter documentation for more details.

❤️ Contributing

For guidelines on contributing, please read the contributing guide.

We welcome contributions from the community to enhance Bunup's capabilities and make it even more powerful.