The first production ready,
and most loved Bun framework

Designed for Humans

Our goal is to design an ergonomic, sensible, and productive framework that even beginners can use easily.

Designed to avoid unnecessary complexity and type complexity for you to focus on building.

A framework that feels just like JavaScript.

import { Elysia, file  } from 'elysia'

new Elysia()
  .get('/', 'Hello World')
  .get('/image', file('mika.webp'))
  .get('/stream', function* () {
    yield 'Hello'
    yield 'World'
  })
  .ws('/realtime', {
    message(ws, message) {
      ws.send('got:' + message)
    },
  })
  .listen(3000)

Type Safety

import { Elysia, t } from 'elysia'

new Elysia()
	.patch('/profile', ({ body }) => body.profile, {




		body: t.Object({
			id: t.Number(),
			profile: t.File({ type: 'image' })
		})
	})
	.listen(3000)

Your own documentation
in 1 line

It's not magic...

With built-in integration with OpenAPI schema, Elysia can generate Swagger documentation for your API out of the box.

import { Elysia } from 'elysia'
import swagger from '@elysiajs/swagger'

new Elysia()
	.use(swagger())
	.use(character)
	.use(auth)
	.listen(3000)

Scalar documentation generated by Elysia using Elysia Swagger plugin

Developer Experience

For DevOps

OpenTelemetry

Elysia has 1st party support for OpenTelemetry. Instrumentation is built-in, so you can easily monitor your services on regardless of the platform.

11.88ms

POST /character/:id/chat

Request

Validation

Transaction

Upload

Sync

For Frontend

End-to-end Type Safety

Like tRPC, Elysia provides type-safety from the backend to the frontend without code generation. The interaction between frontend and backend is type-checked at compile time.

import { treaty } from '@elysiajs/eden'
import type { App } from './server'

const api = treaty<App>('api.elysiajs.com')

const { data } = await api.profile.patch({
    age: 21
})

Performance

21x

faster than Express

6x

faster than Fastify

Elysia Bun
0 reqs/s
Gin Go
0
Spring Java
0
Fastify Node
0
Express Node
0
Nest Node
0

Measured in requests/second. Result from TechEmpower Benchmark, Round 22 (2023-10-17) in PlainText

TypeScript with End-to-End Type Safety, type integrity, and exceptional developer experience. Supercharged by Bun.

The first production ready,and most loved Bun framework

Type Safety

Developer Experience

For DevOps

OpenTelemetry

For Frontend

End-to-end Type Safety

Performance

21x

6x

Elysia Bun

Gin Go

Spring Java

Fastify Node

Express Node

Nest Node

Community

The first production ready,
and most loved Bun framework