Bun

Judgement

What it is

Developer tool

What it does

A JavaScript and TypeScript runtime that aims to replace Node.js, shipped as one executable that also installs packages, bundles code and runs tests.

Adopt it when

You start a new JavaScript or TypeScript project and want fast installs, fast startup and fewer separate tools, and you can test Node compatibility for your dependencies.

Watch out

Node.js API compatibility is close but not complete, so some native modules and edge cases still break, and the company behind it is venture-funded.

Ready for

Production-ready

Runs as

Command line

Built with

Rust, C++, JavaScriptCore and TypeScript

How established

Established: started 5 years ago, latest release bun-v1.4.4.

What the license allows

GitHub could not read the license. Check it in the repository before reusing any code.

Judged on 2026-11-06 from the project's README and GitHub data. The license and age lines are worked out directly.

Built from

Follow it down: Bun → Rust → runs on a microchip

How compilers were built, back to punched paper tape

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