Bun Bundler

If you're bundling JavaScript or TypeScript with Bun instead of webpack or esbuild, this gives Claude the full context on Bun.build. It covers CLI usage, the JavaScript API, code splitting, minification, sourcemaps, custom loaders, and plugin authoring. The documentation is thorough with actual config examples for different targets (browser, Node, Bun runtime) and common patterns like production builds or library packaging. Honest take: Bun's bundler is genuinely fast and the API surface is clean, but the ecosystem is still young. Use this when you're already committed to Bun or need to help Claude troubleshoot builds that aren't working as expected.

skills.sh installs: 334
GitHub stars: 248
last updated: Aug 21, 2026

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Install

$ npx -y skills add secondsky/claude-skills --skill bun-bundler --agent claude-code

Installs into .claude/skills of the current project.

Files

Bun Bundler

Bun's bundler is a fast JavaScript/TypeScript bundler built on the same engine as Bun's runtime. It's an esbuild-compatible alternative with native performance.

Quick Start

CLI

# Basic bundle
bun build ./src/index.ts --outdir ./dist

# Production build
bun build ./src/index.ts --outdir ./dist --minify

# Multiple entry points
bun build ./src/index.ts ./src/worker.ts --outdir ./dist

JavaScript API

// Since Bun 1.2, Bun.build REJECTS on failure (throws).
// Wrap in try/catch to handle errors; pass { throw: false } to restore the
// old resolve-with-{ success, logs } contract if you prefer that style.
try {
  const result = await Bun.build({
    entrypoints: ["./src/index.ts"],
    outdir: "./dist",
  });
  console.log(`Built ${result.outputs.length} files`);
} catch (err) {
  console.error("Build failed:", err);
  process.exit(1);
}

Bun.build Options

await Bun.build({
  // Entry points (required)
  entrypoints: ["./src/index.ts"],

  // Output directory
  outdir: "./dist",

  // Target environment
  target: "browser",  // "browser" | "bun" | "node"

SKILL.md on GitHub