Bun is an all-in-one JavaScript and TypeScript runtime that includes a fast package manager, bundler, test runner, and Node.js-compatible APIs. It natively executes TypeScript and JSX without a separate compilation step.
When to use: Fast server-side JavaScript, TypeScript-first projects, replacing Node.js for better startup performance, built-in SQLite, password hashing, file I/O, HTTP servers, bundling, and testing without external tooling.
When NOT to use: Projects requiring full Node.js ecosystem compatibility (some native modules unsupported), production environments needing battle-tested stability of Node.js, or browser-only code that does not need a runtime.
Bun JavaScript 런타임, 번들러 및 패키지 관리자. Bun.serve() HTTP 서버, Bun.file() I/O, SQLite, 비밀번호 해싱, Bun.build() 번들러, bun:test Runner 및 패키지 관리를 다룹니다. Bun API로 빌드하고, Bun으로 스크립트를 실행하고, 코드를 번들링하고, bun 설치/추가로 패키지를 관리하거나, bun:test로 테스트를 작성할 때 사용합니다. 출처: oakoss/agent-skills.