Bun is a modern JavaScript runtime like Node or Deno. It was built from scratch to focus on three main things:

• Start fast (it has the edge in mind).

• New levels of performance (extending JavaScriptCore, the engine).

• Being a great and complete tool (bundler, transpiler, package manager).

Bun is designed as a drop-in replacement for your current JavaScript & TypeScript apps or scripts — on your local computer, server or on the edge. Bun natively implements hundreds of Node.js and Web APIs, including ~90% of Node-API functions (native modules), fs, path, Buffer and more.

The goal of Bun is to run most of the worlds JavaScript outside of browsers, bringing performance and complexity enhancements to your future infrastructure, as well as developer productivity through better, simpler tooling.

Also an other cool thing is to see that bun really utilizes Zig. A great place to look at high quality Zig code.

Read more here: https://bun.sh/