Procedure

Procedure is a framework-agnostic, type-safe function builder. It allows you to compose middlewares to build up context and validate inputs, then finalize into a callable handler with full type inference.

Why Procedure?

• Type-safe context — Each middleware enriches the context with full TypeScript inference.
• Composable — Reuse middlewares across different procedures and projects.
• Validation — First-class support for Standard Schema (Zod, Valibot, ArkType, etc.).
• Framework Agnostic — Works in any environment: Node.js, Bun, Edge, React Server Components, etc.

Quick Example

import { init } from "@jlnstack/procedure"
import { z } from "zod"

const { procedure, middleware } = init({
  ctx: async () => ({ db: new Database() })
})

const withUser = middleware(({ ctx, next }) => {
  return next({
    ctx: { ...ctx, user: { id: "1", name: "John" } }
  })
})

export const getPost = procedure
  .use(withUser)
  .input(z.object({ id: z.string() }))
  .run(async ({ ctx, input }) => {
    return ctx.db.posts.find(input.id, ctx.user.id)
  })

// Usage
const post = await getPost({ id: "post-123" })