Bun — Development Environment & Programming

Ultra-fast JavaScript/TypeScript runtime and all-in-one development tool

Basic Information

What is this program?

Bun is a JavaScript/TypeScript runtime built on Apple’s JavaScriptCore engine. It offers Node.js-compatible APIs while significantly improving startup and execution speed.

It is not just a runtime — it also includes a package manager (bun install), test runner (bun test), and bundler (bun build). It is especially well suited to environments where you can control the dependency scope yourself, such as new projects, CLI tools, and serverless functions.

What problems does it solve?

• When you need to speed up build and execution times for Node.js-based projects
• When you want package management, testing, and bundling in one tool without a separate toolchain
• When lightweight, fast execution matters, such as for CLI tools or serverless functions

Key Features

High-performance runtime

Provides fast startup and execution speed based on JavaScriptCore

• Use case: Reduced script and server execution time
• Result: Higher HTTP throughput compared to Node.js
• Limitations: Limited compatibility with Node.js-only native modules

Built-in package manager

Provides bun install compatible with package.json

• Use case: Faster dependency installation
• Result: Reduced node_modules installation time
• Limitations: Compatibility with some ecosystem tools needs to be verified

Built-in tester and bundler

Use bun test and bun build for testing and bundling without separate tools

• Use case: Simplified toolchain
• Result: Run tests with minimal configuration
• Limitations: Limited compatibility with advanced Jest/Webpack configuration

Native TypeScript

Run TypeScript directly without separate compilation

• Use case: Faster onboarding for TS projects
• Result: Run immediately after file edits
• Limitations: Type checking is recommended with a separate tool

Installation and Execution

Official installation script

Install on Linux and macOS using the curl script.

curl -fsSL https://bun.sh/install | bash

npm

If you have a Node.js environment, you can also install it with npm.

npm install -g bun

Windows

Use the PowerShell installation script.

powershell -c "irm bun.sh/install.ps1 | iex"

Practical Usage Examples

Running a script

Run TypeScript and JavaScript files directly.

bun run index.ts

Installing dependencies

Install quickly based on package.json.

bun install

Running tests

Run tests with the built-in tester.

bun test

Advantages and Limitations

Advantages

• Simplifies the toolchain by integrating runtime, package management, testing, and bundling
• Fast execution performance based on JavaScriptCore
• Open source under the MIT License
• Node.js-compatible API enables gradual migration

Things to Consider Before Using

• Compatibility with Node.js-only native addons is not perfect
• For large legacy systems, the proven Node.js ecosystem may still be safer
• Support policy is not clear, and updates are frequent

Comparison with Similar Programs

Official Resources and Further Learning

• Official website — https://bun.com/
• Official documentation / knowledge base — https://bun.com/docs
• Official download — https://bun.com/docs/installation
• Release notes — https://bun.com/blog
• Source / development resources — https://github.com/oven-sh/bun

Version and supported environment information was verified on the official site as of 2026-10-18. Installation commands may vary depending on your distribution and version, so please also check the official installation documentation.

Actual Execution Screen

Composite example — not an actual execution result. The screen is a composite example and not an actual execution result.

!Example of checking the Bun version, running a script, and installing a package

A server in actual operation

Source (HTML): https://games.aidebatehub.com/programs/apps/dev/bun.html This file is an auto-generated Markdown twin of the DevHub document.