Bun Docs

Bun — Skill Documentation

Metadata

• Target Version: Bun 1.2.x
• Source: bun.sh/docs
• Files: 9
• Lines: ~4,350

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Quick Reference

| Topic | File | Description | |-------|------|-------------| | Getting Started (installation, quickstart, TypeScript, bun init) | getting-started.md | Install Bun, create projects, run TS/JSX | | Runtime (execution, watch mode, REPL, bunfig, modules, plugins) | runtime.md | bun run, file types, module resolution, auto-install | | Package Manager (bun install, add, remove, update, publish, outdated, why, audit, info, link, patch, workspaces, catalogs, filter, scopes, npmrc, security scanner, global cache, isolated installs) | package-manager.md | Full PM: install, update, publish, audit, patch, catalogs, isolated installs | | HTTP Server (Bun.serve, routing, HTML imports, WebSockets, TLS) | http-server.md | Built-in HTTP server, file-system routing, hot reload | | APIs (File I/O, SQLite, Streams, Fetch, Workers, Shell, Utils, Globals, Web APIs, Bun APIs reference) | apis.md | Bun.file, Bun.write, bun:sqlite, Bun.spawn, Workers, utils, compression, globals | | Advanced APIs (SQL, S3, Redis, TCP/UDP, Cron, FFI, Image, Archive, WebView, Cookies, CSRF, JSON5, Transpiler, Node.js compat) | advanced-apis.md | PostgreSQL/MySQL, S3 storage, Redis, TCP/UDP sockets, cron jobs, FFI, image processing, tar archives | | Testing (bun test, assertions, mocks, snapshots, watch mode) | testing.md | Jest-compatible test runner, TypeScript-first | | Bundler (bun build, targets, plugins, executables, HTML imports) | bundler.md | Native bundler for browser/bun/node, single-file executables |

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What is Bun?

Bun is an all-in-one toolkit for developing modern JavaScript/TypeScript applications:

• Runtime: Execute JS/TS files with near-zero overhead (JavaScriptCore engine)
• Package Manager: Fast installs with bun install — replacement for npm/yarn/pnpm
• Test Runner: Jest-compatible, TypeScript-first tests with bun test
• Bundler: Native bundling for JS/TS/JSX with bun build

bun run index.tsx    # TS and JSX supported by default
bun run start        # run the `start` script
bun install     # install a package
bun build ./index.tsx # bundle a project for browsers
bun test             # run tests
bunx cowsay 'Hello'  # execute a package

Design Goals

• Speed: Bun processes start 4x faster than Node.js
• TypeScript & JSX: Directly execute .ts, .tsx, .jsx files
• ESM & CommonJS: Recommends ES modules, supports CommonJS
• Web-standard APIs: fetch, WebSocket, ReadableStream, Headers, URL
• Node.js compatibility: Built-in globals (process, Buffer) and modules (path, fs, http)

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Common Patterns

Create a new project

bun init my-app
cd my-app
bun run index.ts

Start an HTTP server

const server = Bun.serve({
  port: 3000,
  routes: {
    "/": () => new Response("Bun!"),
    "/users/:id": req => new Response(`Hello User ${req.params.id}!`),
  },
});
console.log(`Listening on ${server.url}`);

Read and write files

const file = Bun.file("input.txt");
const text = await file.text();

await Bun.write("output.txt", "Hello, world!");

Use SQLite

import { Database } from "bun:sqlite";
const db = new Database("mydb.sqlite");
const query = db.query("SELECT * FROM users WHERE id = ?");
const user = query.get(1);

Write and run tests

import { expect, test } from "bun:test";

test("2 + 2", () => {
  expect(2 + 2).toBe(4);
});

bun test

Bundle for production

bun build ./index.tsx --outdir ./out

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: pledgeandgrow
• Source: pledgeandgrow/pledge-skills
• License: MIT

Install and usage instructions live in the source repository linked above.