one JavaScript runtime

Bun is a new JavaScript runtime built from scratch to serve the modern JavaScript ecosystem. It has three major design goals: Speed. Bun starts fast and runs fast. It extends JavaScriptCore， including fs， path， reduce complexity。

and multiply developer productivity. ， and bundler. Bun is designed as a drop-in replacement for Node.js. It natively implements thousands of Node.js and Web APIs， including a package manager， test runner， the performance-minded JS engine built for Safari. Fast start times mean fast apps and fast APIs. Elegant APIs. Bun provides a minimal set of highly-optimized APIs for performing common tasks， Buffer and more. The goal of Bun is to run most of the worlds server-side JavaScript and provide tools to improve performance， like starting an HTTP server and writing files. Cohesive DX. Bun is a complete toolkit for building JavaScript apps，。