Bun is a fast all-in-one JavaScript runtime

https://bun.sh/

Node.js や Deno のように、ブラウザ以外で動作する新しい JavaScript ランタイム。

A challenger appears! Bun is a new JavaScript runtime built not around V8 (like Node.js or Deno are) but WebKit/Apple’s JavaScriptCore. It includes its own bundler, transpiler, task runner, and npm client, but most significantly boasts huge performance improvements over existing options and supports a lot of Node and Web APIs already. Want a quick tour and explanation? ▶️ This video by Theo of ping.gg does a pretty good job. One to watch.
https://nodeweekly.com/issues/445

ただ、まだ未実装の機能も多そうで、まだ余分なものがないから速いのもあるかもしれない。
参考: https://twitter.com/kt3k/status/1545706938997940225