Privacy Policy

What We Collect

When you sign in, we receive your Twitch account information (display name and avatar) via OAuth. We do not store your password or any Twitch credentials directly.

Local Storage

Your game ROM is stored in your browser's IndexedDB. Save states are stored locally on your device. None of this data is uploaded to our servers unless you explicitly use co-op features, in which case save data may be temporarily stored server-side to enable session resumption.

Cookies

We use a session cookie for authentication via Supabase. We do not use tracking cookies, analytics cookies, or any third-party cookies.

Third-Party Services

We use Supabase for authentication and Vercel for hosting. Both services have their own privacy policies. We do not share your data with any other third parties.

Data Retention

Your account data is persisted for as long as your account exists. Game data (ROM, save states) is local to your browser and is not retained by us. Co-op session data is temporary and deleted after the session ends.

Contact

For questions about this privacy policy or your data, reach out via GitHub issues on the UltraKaizo repository.

Last updated: March 24, 2026