Deploy to Vercel#

The same layout as Cloudflare (site at /, /app/, /chat/, the API at /api/v1/*), deployed as a prebuilt Vercel Build Output API v3 tree. Nothing builds on Vercel's side and no vercel.json is needed.

Build and deploy#

npm run build:vercel                  # writes .vercel/output/ (gitignored)
npx vercel deploy --prebuilt          # preview deployment
npx vercel deploy --prebuilt --prod   # production

The first vercel deploy asks you to log in and to link or create a project; accept the defaults. Add provider keys in the project's Settings, Environment Variables (the same names as .env.example), or with npx vercel env add GROQ_API_KEY.

What gets built#

Path in `.vercel/output/`	Content
`static/`	the assets tree from `deploy/serverless/lib/assets.mjs` (same as Cloudflare)
`functions/api.func/index.mjs`	the HTTP API bundled into one ESM file with esbuild, Node.js 22 runtime
`functions/api.func/.vc-config.json`	runtime settings (`nodejs22.x`, streaming responses on)
`config.json`	routes, in order: `/api/`, `/mcp` and `/.well-known/oauth-` to the function; files; app fallbacks (`/app/` and `/chat/` serve their `index.html` for paths that do not look like files); then `404.html`

The function is deploy/serverless/vercel/function.ts: createApp from packages/server wrapped with getRequestListener from @hono/node-server. It reads env from process.env and uses Vercel's x-real-ip header (which Vercel sets and clients cannot spoof) for per-IP rate limits.

The build uses esbuild, which is already installed with tsx and vitest. It should become a declared root devDependency (prompt 38 owns those).

What runs on Vercel#

The function uses the fetch-only provider set (the same one the Cloudflare Worker runs), deliberately not the Node registry:

Works	Does not
YouTube metadata and captions	yt-dlp, ffmpeg, whisper.cpp and local models (no binaries, short-lived functions)
Hosted and keyless speech-to-text for small uploads (request bodies are capped at 4.5 MB on Vercel)	Reading local files: a public function must never read the server's filesystem, so `?url=/etc/passwd` is refused with 400
Every hosted and keyless LLM rung	Long jobs: Hobby functions stop after 60 seconds by default

Use the Docker deploy (deploy/containers/, prompt 49) when you need yt-dlp, ffmpeg or local models on a server.

Verified locally#

deploy/serverless/test/targets.test.ts builds the output, loads the bundled function into a real Node HTTP server, checks /api/v1/health and the local-path refusal, and checks the route order. On 2026-11-14 the route table also passed Vercel's own validator (normalizeRoutes from @vercel/routing-utils 6.6.1). The Vercel CLI was not installed on the build machine, so vercel build and a real deployment have not been run.