Skip to main content

Deploy on Vercel

Deploy BurgerAPI to Vercel as a web-standard Function. The same WinterCG entry works on Vercel, Cloudflare Workers, and Deno; only the entry file and platform config differ.

How it works​

  • api/index.ts exports the Vercel web-standard shape: export default { fetch: toFetchHandler(burger) } on the Node.js runtime (export const runtime = "nodejs").
  • vercel.json rewrites every path to /api, so toFetchHandler does the routing: dynamic params, 404s, and method handling all work as they do on Bun.
  • Routes are declared via apiRoutes (AOT). Vercel Functions have no filesystem, so there is no runtime route scanning.
  • The module graph contains no bun imports.

Quick start: burger-api build --target=vercel​

If you're using file-based routing, the CLI generates the api/index.ts entry and vercel.json below for you:

burger-api build src/index.ts --target=vercel
vercel dev

The build fails at this step if your project has any WebSocket routes, because Vercel Functions have no persistent-connection model to upgrade into (see Compatibility). The rest of this page shows the equivalent by hand, useful if you're declaring routes programmatically instead of via the file convention.

Unlike the cloudflare/deno targets (whose output lands under .build/, which tsc's default file discovery skips), Vercel's zero-config detection requires the generated entry at api/index.ts, inside your normal source tree. If you run tsc --noEmit across the whole project, add "exclude": ["api"] to tsconfig.json so it doesn't typecheck the generated (unannotated) output.

Entry file​

// api/index.ts
import { Burger } from "burger-api";
import { toFetchHandler } from "burger-api/adapter/web-standard";
import type { BurgerContext } from "burger-api";

const burger = new Burger({
  title: "My API on Vercel",
  description: "Deploy the same code to any WinterCG runtime",
  apiRoutes: [
    {
      path: "/api/hello",
      handlers: {
        GET: (ctx: BurgerContext) =>
          Response.json({ message: "Hello from Vercel!" }),
      },
      openapi: { get: { summary: "Greeting", tags: ["hello"] } },
    },
    {
      path: "/api/users/:id",
      handlers: {
        GET: (ctx: BurgerContext) => Response.json({ id: ctx.params?.id }),
      },
      openapi: { get: { summary: "Get user by id", tags: ["users"] } },
    },
  ],
});

export const runtime = "nodejs";

export default { fetch: toFetchHandler(burger) };

vercel.json​

{
  "rewrites": [
    {
      "source": "/(.*)",
      "destination": "/api"
    }
  ]
}

Run locally​

npx vercel dev

Deploy​

npx vercel --prod