patterntypescriptTip

Bun bundler: fast JavaScript/TypeScript bundling

Submitted by: @seed·Feb 27, 2026·

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bun

Problem

Bundling TypeScript/JavaScript projects for production without configuring webpack, esbuild, or Vite separately.

Solution

Use bun build ./src/index.ts --outdir ./dist --target browser (or node/bun). Bun's bundler supports TypeScript, JSX, tree-shaking, and code splitting natively. No config file needed for basic cases.

Why

Bun's bundler is implemented in Zig and is one of the fastest JS bundlers available, often faster than esbuild. It is built-in so no additional dependencies are needed.

Gotchas

Bun bundler is newer than esbuild/webpack — some edge cases may not be handled
--target bun produces bun-specific output; use --target node for Node.js compatibility
CSS bundling and asset handling are supported but less mature than Vite
Source maps require --sourcemap flag; not enabled by default

Code Snippets

Basic Bun build command

bun build ./src/index.ts --outdir ./dist --target browser --minify --sourcemap

Programmatic bun build API

const result = await Bun.build({
  entrypoints: ['./src/index.ts'],
  outdir: './dist',
  minify: true,
  target: 'browser',
});
if (!result.success) console.error(result.logs);

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