Elysia

Elysia is what happens when you build a web framework specifically for Bun and stop caring about Node.js compatibility. The result: 2.5M requests per second, end-to-end type safety between server and client via Eden (no codegen), and an API that makes Express feel like writing COBOL.

If you're building APIs on Bun and want the fastest possible framework with TypeScript-native ergonomics, Elysia is it. Hono is the portable alternative — same code runs on Cloudflare Workers, Deno, Bun, and Node — but it's slower on Bun and lacks Eden's type-safe client. Express has 30M weekly downloads and no excuse to still exist in new projects. Fastify is the mature Node.js option.

The catch: Elysia means Bun. Not "Bun optional" — Bun required in production. That's a runtime bet most teams aren't ready to make. If Bun hits a bug in your deployment, your framework can't save you. And with 500K weekly downloads versus Hono's 1.8M, the ecosystem and hiring pool are significantly smaller.