# Bun

Incredibly fast JavaScript runtime, bundler, test runner, and package manager – all in one

Repository: https://github.com/oven-sh/bun
Canonical: https://ross.abutalabs.com/products/bun
Homepage: https://bun.com
Language: Rust
License: NOASSERTION
License Family: other
Topics: bun, bundler, javascript, javascriptcore, jsx, nodejs, npm, react, transpiler, typescript, rust, rust-lang
Last push: 2026-08-27T00:41:43+00:00

## Health v2 (maintenance only)
Score: 99/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 99, release rhythm 98, longevity 100
- inputs: {"age_days": 1968, "days_push": 7, "days_rel": 13, "gap_med": 10.5, "n_releases_24m": 59}
- flags: no_license
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 95716, forks 5004 (observed 2026-08-28T04:12:23.586417+00:00)

## What it is
Bun is an all-in-one JavaScript and TypeScript toolkit that ships as a single executable combining a fast runtime, bundler, test runner, and npm-compatible package manager. It is written in Rust, powered by JavaScriptCore, and designed as a drop-in replacement for Node.js with dramatically faster startup and install times.

## Use cases
- run typescript and jsx files directly without a build step
- install npm packages faster than npm or yarn
- replace node.js as a javascript runtime
- run javascript tests with a built-in test runner
- bundle javascript and typescript apps
- run package.json scripts
- execute packages with npx-like tooling

## When to choose
- you want a fast drop-in Node.js replacement with TypeScript support out of the box
- you need a single tool replacing runtime, bundler, test runner, and package manager
- install speed and startup time matter for your workflow or CI

## When to avoid
- you depend on native Node.js addons or APIs Bun does not fully support
- your production stack requires long-term Node.js LTS compatibility
- you rely on ecosystem tooling that assumes Node.js internals

## Facets
- artifact type: cli-tool
- maturity: active
- function: programming-language, package-manager, build-tool, testing, http-server, cli
- domain: developer-tools, web-development
- platform: windows, cli
- tags: javascript-runtime, typescript, jsx, transpiler, bundler, nodejs-alternative, javascriptcore, all-in-one-toolkit, javascript, command-line, linux, macos, docker

## Member repositories
- oven-sh/bun (main) score 99
- oven-sh/awesome-bun (docs) score 47

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:12:23.586417+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T16:12:38.009198+00:00, confidence not recorded.
  - readme: https://github.com/oven-sh/bun (fetched 2026-08-28T04:12:23.586417+00:00, sha afab83f09877)
- Data as of 2026-08-30T08:39:29.467469+00:00.