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Bun

All-in-one JavaScript runtime and toolkit

Bun is an all-in-one JavaScript runtime, bundler, transpiler, package manager, and test runner built from scratch in Zig for maximum performance. Starts and runs JavaScript/TypeScript up to 4x faster than Node.js with native support for JSX, TypeScript, and ESM without configuration. npm-compatible package manager installs dependencies 25x faster. Includes a built-in SQLite database, HTTP server, WebSocket support, and file I/O APIs. Drop-in Node.js replacement for most use cases.

About Bun

Bun is a complete JS/TS runtime built in Zig combining runtime, bundler, transpiler, package manager, and test runner in a single binary replacing Node.js, npm, Webpack, Babel, and Jest.

4x faster JS execution via JavaScriptCore engine. Package installs 25x faster than npm. Native TypeScript, JSX, and ESM without configuration.

Built-in SQLite database, HTTP/WebSocket server, and file I/O APIs. Growing Node.js API compatibility with most npm packages working as drop-in replacement.

Pricing & Platform Specs

Pricing Summary

All-in-one ultra-fast JavaScript and TypeScript runtime, package manager, bundler, and test runner. Free and 100% open source under the MIT License ($0 software cost). Has zero commercial licensing fees or usage restrictions across local development, CI/CD, and production workloads.

full pricing breakdown →

Supported Platforms

macOS, Linux, Windows (WSL)

Explore categories, tags & use cases

Alternatives

All Bun alternatives →

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Open-source background jobs and AI workflows for TypeScript

Trigger.dev is an open-source platform for building and deploying background jobs, AI agents, and long-running workflows in TypeScript. It eliminates serverless timeouts with durable task execution, automatic retries, queue-based concurrency control, and elastic scaling. Used by 30,000+ developers at companies like MagicSchool and Icon.com, it processes hundreds of millions of agent runs monthly. Backed by a $16M Series A led by Dalton Caldwell's Standard Capital fund.

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Open-source PaaS alternative to Vercel, Heroku, and Netlify

Dokploy is a free open-source platform-as-a-service for self-hosting applications without cloud vendor lock-in. It provides automated deployments from Git repositories, built-in SSL certificates, database provisioning, Docker and Docker Compose support, and a clean web dashboard for managing multiple applications on your own servers. With 18,000+ GitHub stars, it fills the gap for teams wanting Vercel-like deployment simplicity on their own infrastructure.

freemiumOpen Source

Community experience

Sources & verification

Sources checked
Content verified

Verification dates are editorial checks. Routine CMS saves and automatic updatedAt timestamps do not advance them.

FAQ

What is Bun?

Bun is an all-in-one JavaScript runtime, bundler, transpiler, package manager, and test runner built from scratch in Zig for maximum performance. Starts and runs JavaScript/TypeScript up to 4x faster than Node.js with native support for JSX, TypeScript, and ESM without configuration. npm-compatible package manager installs dependencies 25x faster. Includes a built-in SQLite database, HTTP server, WebSocket support, and file I/O APIs. Drop-in Node.js replacement for most use cases.

Is Bun free?

Yes — Bun is open source and free to use. All-in-one ultra-fast JavaScript and TypeScript runtime, package manager, bundler, and test runner. Free and 100% open source under the MIT License ($0 software cost). Has zero commercial licensing fees or usage restrictions across local development, CI/CD, and production workloads.

Is Bun open source?

Yes — Bun is open source.

Is Bun still maintained?

Yes — Bun is active. Its listing was last verified on September 6, 2026.

What are the best Bun alternatives?

The first editor-selected Bun alternatives are Steel, Trigger.dev, Dokploy.