Start RC - Server Route Redirects not working with Nitro v3 in development

[dotnize]

Which project does this relate to?

Start

Describe the bug

Redirects with Server Route handlers (API routes) are not working in development when using the Nitro v3 (nitro-nightly) plugin. This is also probably breaking OAuth flows as they typically involve a couple redirects.

Only in development. I tested with a local Node.js build and Vercel deployment and it works fine.

Not sure if this is a Start issue or just with Nitro.

Your Example Website or App

https://github.com/dotnize/ts-start-nitrov3-response-utils

Steps to Reproduce the Bug or Issue

1. Run app in dev
2. Go to /api/test or /api/test2 - error will show

Expected behavior

Redirect to specified url in development

Screenshots or Videos

ℹ HTTPError: fetch failed

 ⁃ (node:internal/deps/undici/undici:13510:13)
 ⁃ at processTicksAndRejections (node:internal/process/task_queues:105:5)
 ⁃ at fetchHandler (node_modules/.pnpm/nitro-nightly@3.0.0-20250924-113752-9fe8cd46_vite@7.1.7_@types+node@22.18.6_jiti@2.6.0__f3fc809ec029dafbeaa607130fd159a4/node_modules/nitro-nightly/dist/runtime/internal/app.mjs:52:22)

   47 ┃      const event = { req };
   48 ┃      const nitroApp = useNitroApp();
   49 ┃      await nitroApp.hooks.callHook("request", event).catch((error) => {
   50 ┃        captureError(error, { event, tags: ["request"] });
   51 ┃      });
 ❯ 52 ┃      const response = await h3App.request(req, void 0, req.context);
   53 ┃      await nitroApp.hooks.callHook("response", response, event).catch((error) => {
   54 ┃        captureError(error, { event, tags: ["request", "response"] });
   55 ┃      });
   56 ┃      return response;
   57 ┃    };

 ⁃ (node_modules/.pnpm/nitro-nightly@3.0.0-20250924-113752-9fe8cd46_vite@7.1.7_@types+node@22.18.6_jiti@2.6.0__f3fc809ec029dafbeaa607130fd159a4/node_modules/nitro-nightly/dist/runtime/internal/vite/worker.mjs:88:16)

[CAUSE]
TypeError {
  stack: 'fetch failed\n' +
  '    at node:internal/deps/undici/undici:13510:13\n' +
  '    at processTicksAndRejections (node:internal/process/task_queues:105:5)\n' +
  'at fetchHandler (./node_modules/.pnpm/nitro-nightly@3.0.0-20250924-113752-9fe8cd46_vite@7.1.7_@types+node@22.18.6_jiti@2.6.0__f3fc809ec029dafbeaa607130fd159a4/node_modules/nitro-nightly/dist/runtime/internal/app.mjs:52:22)\n' +
  'at ./node_modules/.pnpm/nitro-nightly@3.0.0-20250924-113752-9fe8cd46_vite@7.1.7_@types+node@22.18.6_jiti@2.6.0__f3fc809ec029dafbeaa607130fd159a4/node_modules/nitro-nightly/dist/runtime/internal/vite/worker.mjs:88:16)',
  message: 'fetch failed',
  cause: Error {
    stack: 'C0963F55217F0000:error:0A0000C6:SSL routines:tls_get_more_records:packet length too long:../deps/openssl/openssl/ssl/record/methods/tls_common.c:662:\n' +
    '\n' +
    'at Error: C0963F55217F0000:error:0A0000C6:SSL routines:tls_get_more_records:packet length too long:../deps/openssl/openssl/ssl/record/methods/tls_common.c:662::undefined:undefined)',
    message: 'C0963F55217F0000:error:0A0000C6:SSL 
    routines:tls_get_more_records:packet length too 
    long:../deps/openssl/openssl/ssl/record/methods/tls_common.c:662:\n',
    library: 'SSL routines',
    reason: 'packet length too long',
    code: 'ERR_SSL_PACKET_LENGTH_TOO_LONG',
  },
}

Platform

• Router / Start Version: 1.132.6
• OS: Linux
• Browser: Chrome 140
• Bundler: Vite 7.1.7
• Node version: 22.20.0

Additional context

setResponseHeader("Location", "https://tanstack.com");
return new Response(null, { status: 302 });

return Response.redirect("https://tanstack.com");

package.json

"nitro": "npm:nitro-nightly@latest",

vite config

+ import { nitro } from 'nitro/vite'

export default defineConfig({
  server: {
    port: 3000,
  },
  plugins: [
    tsConfigPaths(),
    tanstackStart(),
+   nitro(),

[nandcello]

I'm also experiencing this when using the cloudflare vite plugin.

[dotnize]

Just upgraded to latest Start and Nitro ^3.0.1-alpha.0 and it now seems to be fixed!

Opened a PR to update the Nitro v3 instructions:

• docs(start): update nitro v3 instructions for nitro alpha package #5453