---
title: Bun
description: Serve the Files gateway from Bun.serve. The gateway's handle(req) is already a Web fetch handler, so it drops straight into a route - no adapter needed.
---

`Bun.serve` hands your handler a Web `Request` and sends back whatever `Response` you return — which is exactly the shape the gateway speaks (`handle(req: Request): Promise<Response>`). So there is no `files-sdk/bun` adapter to import: drop [`router.handle`](/ui/server/gateway) straight into a route.

```ts title="server.ts" lineNumbers
import { createFiles } from "files-sdk";
import { s3 } from "files-sdk/s3";
import { createFilesRouter } from "files-sdk/api";

const router = createFilesRouter({
  files: createFiles({ adapter: s3({ bucket: "uploads" }) }),
  allowedOrigins: ["https://app.example.com"],
  authorize: async ({ req }) => {
    /* throw to deny, or return a per-user constraint — see /ui/server/authorization */
  },
});

Bun.serve({
  port: 3000,
  routes: {
    // A bare handler runs for every method; the gateway dispatches internally
    // (GET = download, POST = the JSON verbs, PUT = upload).
    "/api/files": (req) => router.handle(req),
  },
});
```

<Callout>
  Want routing and middleware on Bun? [Hono](/ui/server/hono) and
  [Elysia](/ui/server/elysia) both run on Bun and have their own bindings — the
  gateway is the same underneath.
</Callout>

See the [gateway options](/ui/server/gateway) for the full configuration and the [`authorize`](/ui/server/authorization) model for locking it down.