Your machine. Your keys.

Prefer not to enter a key on a hosted website? Inspect the open-source code and run the same interface on your computer.

Start the web app

Install Node.js 22 LTS and Git, then run:

git clone https://github.com/chenmingtang830/jevarena.git
cd jevarena/web
npm ci
npm run dev

Open 127.0.0.1:3000/play. Enter a dedicated provider key only when you are ready to run. Keys remain in the tab’s memory and are cleared on refresh.

Local does not mean offline

Model providers still receive the task and your key, and calls still use your provider balance. Local execution removes the hosted JevArena page from that path; it does not remove the need to trust the code, dependencies, browser, or model provider.

Use a Vercel AI Gateway key locally

Stop the development server, then restart with the local relay enabled:

NEXT_PUBLIC_VERCEL_BYOK_ENABLED=true JEVARENA_RELAY_ENABLED=true npm run dev

In the connection dialog, expand “Use an API key instead” and select Vercel AI Gateway. Use an AI Gateway key, not a Vercel account token. Your local server forwards the request to Vercel; the key is not saved. Starting the server does not call a model. Clicking Start judging uses your credits.

This command binds to your computer only. Do not expose or deploy this relay publicly; public deployment needs separate shared rate limiting and operational review. See the provider setup.

Use a separate low-limit key, revoke it after testing, and never commit it. Research submission and public sharing are separate, optional actions.