Bun
What it is
Bun combines a JavaScript and TypeScript runtime, package manager, test runner, and bundler in one binary. The runtime uses JavaScriptCore and supports Node.js APIs and node_modules. Its npm-compatible package manager supports workspaces, catalogs, overrides, patches, and a readable lockfile, as well as private registry authentication and offline installation. The test runner includes Jest-compatible expectations, mocks, snapshots, DOM testing, and coverage. Bun’s bundler handles TypeScript, JSX, CSS, and HTML for browsers and servers, and includes a development server with hot module reloading and single-file executables. Built-in APIs cover databases, Redis, S3-compatible storage, HTTP, and WebSockets. Bun names Next.js, Remix, Nuxt, Astro, SvelteKit, Hono, and Elysia as compatible frameworks. It is free, open-source, and MIT-licensed, with development on GitHub. Bun runs on macOS, Linux, and Windows, subject to minimum system and processor requirements. Install options include an official script, npm, Homebrew, Windows package managers, and Docker.
For and against
For
- Combines four JavaScript tools in one binary
- Supports Node.js APIs and node_modules
- Package manager supports workspaces and offline installation
- Test runner includes snapshots and coverage
- Offers multiple installation options
Against
- Requires macOS 13.0 or later
- Windows requires version 10 1809 or later
- Requires an x64 CPU with SSE4.2 support
The verdict
Bun brings runtime, package management, testing, and bundling together, with built-in APIs and framework compatibility. Check the operating-system and processor requirements before installing.
Who it suits
Bun suits developers who want runtime, package management, testing, and bundling in one toolkit. It is available for macOS, Linux, and Windows users who meet its system requirements.
Plans and prices
Bun
Open-source JavaScript runtime and toolkit · MIT-licensed
Read 7 Oct 2026 · bun.sh
On the record
- Built-in integrations
- Bun includes APIs for PostgreSQL, MySQL, SQLite, Redis, S3-compatible storage, HTTP, and WebSockets.bun.sh · read 7 Oct 2026
- Bundling
- Bun’s bundler handles TypeScript, JSX, CSS, and HTML for browsers and servers, and supports a dev server with hot module reloading and single-file executables.bun.sh · read 7 Oct 2026
- Company
- Bun says it has joined Anthropic, which is investing in Bun as infrastructure for Claude Code, Claude Agent SDK, and future AI coding products.bun.sh · read 7 Oct 2026
- Dependency resolution
- Yesbun.sh · read 21 Sep 2026
- Framework compatibility
- The site names Next.js, Remix, Nuxt, Astro, SvelteKit, Hono, and Elysia as frameworks that run on Bun.bun.sh · read 7 Oct 2026
- Install options
- The install page offers installation through an official script, npm, Homebrew, Windows package managers, and Docker.bun.sh · read 7 Oct 2026
- Lockfile support
- Yesbun.sh · read 21 Sep 2026
- Offline installation
- Yesbun.sh · read 21 Sep 2026
- Open source
- Bun says it remains open-source and MIT-licensed and continues to be developed in public on GitHub.bun.sh · read 7 Oct 2026
- Package formats
- npm packages,Git repositories,GitHub repositories,tarballs,file dependencies,npm aliasesbun.sh · read 21 Sep 2026
- Package manager
- Bun’s npm-compatible package manager supports workspaces, catalogs, overrides, patches, and a readable lockfile.bun.sh · read 7 Oct 2026
- Platform limits
- Bun requires macOS 13.0 or later, Windows 10 version 1809 or later, and x64 CPUs with SSE4.2 support.bun.sh · read 7 Oct 2026
- Private registry auth
- Yesbun.sh · read 21 Sep 2026
- Runtime
- Bun runs JavaScript and TypeScript on JavaScriptCore and supports Node.js APIs and node_modules.bun.sh · read 7 Oct 2026
- Security features
- Bun lists password hashing with Argon2 and bcrypt, CSRF tokens, and OS keychain secrets storage among its built-in APIs.bun.sh · read 7 Oct 2026
- Support
- Bun directs users to its Discord for support and discussion.bun.sh · read 7 Oct 2026
- Supported platforms
- macOS,Linux,Windowsbun.sh · read 21 Sep 2026
- Testing
- Bun’s test runner offers Jest-compatible expectations, mocks, snapshots, DOM testing, and coverage.bun.sh · read 7 Oct 2026
