Create backend with ElysiaJS, a type-safe, high-performance framework.
Always consult elysiajs.com/llms.txt for code examples and latest API.
ElysiaJS is a TypeScript framework for building Bun-first (but not limited to Bun) type-safe, high-performance backend servers. This skill provides comprehensive guidance for developing with Elysia, including routing, validation, authentication, plugins, integrations, and deployment.
Trigger this skill when the user asks to:
Quick scaffold:
bun create elysia app
import { Elysia, t, status } from 'elysia'
const app = new Elysia()
.get('/', () => 'Hello World')
.post('/user', ({ body }) => body, {
body: t.Object({
name: t.String(),
age: t.Number()
})
})
.get('/id/:id', ({ params: { id } }) => {
if(id > 1_000_000) return status(404, 'Not Found')
return id
}, {
params: t.Object({
id: t.Number({
minimum: 1
})
}),
response: {
200: t.Number(),
404: t.Literal('Not Found')
}
})
.listen(3000)
import { Elysia } from 'elysia'
new Elysia()
.get('/', 'GET')
.post('/', 'POST')
.put('/', 'PUT')
.patch('/', 'PATCH')
.delete('/', 'DELETE')
.options('/', 'OPTIONS')
.head('/', 'HEAD')
.get('/user/:id', ({ params: { id } }) => id)
.get('/post/:id/:slug', ({ params }) => params)
.get('/search', ({ query }) => query.q)
// GET /search?q=elysia → "elysia"
.post('/user', ({ body }) => body)
.get('/', ({ headers }) => headers.authorization)
import { Elysia, t } from 'elysia'
.post('/user', ({ body }) => body, {
body: t.Object({
name: t.String(),
age: t.Number(),
email: t.String({ format: 'email' }),
website: t.Optional(t.String({ format: 'uri' }))
})
})