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Bun

A fast JS runtime Node.js replacement with built‑in tools

Bun preview

What is Bun

Bun is a high-performance JavaScript runtime designed as a modern alternative to Node.js, integrating essential development tools such as a bundler, transpiler, test runner, and package manager into a single executable. It is built from scratch using Zig and JavaScriptCore to achieve faster startup times, reduced memory usage, and aims for full compatibility with the Node.js ecosystem, supporting JavaScript, TypeScript, and JSX out-of-the-box.

Key Features

Fast JavaScript runtime optimized for performance and low memory usage
Built-in bundler and transpiler for JavaScript and TypeScript projects
Native test runner that accelerates testing with benchmarks showing 10-30x speed improvements
Npm-compatible package manager for rapid dependency installation, up to 30x faster than alternatives
Single executable with integrated tools for a streamlined development workflow

Use Cases

  • JavaScript developers seeking a faster runtime and toolchain to replace Node.js for application development
  • Teams using TypeScript or modern frameworks who need integrated bundling, testing, and package management
  • Open-source projects that benefit from a unified, high-performance toolkit for building and maintaining code
  • Companies optimizing CI/CD pipelines to reduce build and test times for faster deployments

Why do startups need this tool?

Startups need Bun to accelerate development cycles through its integrated, high-performance toolchain, reducing time spent on building, testing, and deploying applications. Faster iterations and simplified setup help small teams move quickly and efficiently, optimizing resource usage and enabling rapid product evolution in competitive markets.

FAQs

Bun Alternatives

Node.js
Deno
Vite
Jest
npm