We use your browser's Local Storage strictly for gameplay functionality. This allows you to close the tab and return later without losing your progress.

• What is stored: Your current puzzle state, win streak, audio settings, and "solved" history.
• Privacy: By default, this data resides entirely on your device. If you opt into Cloud Saves, we upload an anonymous copy of your game state and statistics to our database so you can sync across devices.
• Cloud Saves (optional): If enabled, we store your game state and statistics under a random Save ID (no account required). We do not attach your Save ID to your name, email, or a user profile. The Save ID is the only credential used to retrieve a cloud save, so treat it like a password. Saves are refreshed when you finish a puzzle and expire after 1 year of inactivity.
• Leaderboards (optional, requires Cloud Saves): If you enable Cloud Saves and choose to set a nickname, your puzzle scores can appear on global and group leaderboards. Only your chosen nickname and scores are displayed – no other personal information is shared. You can change or remove your nickname at any time, and you control which groups you join.
• Control: You can wipe this data at any time by clearing your browser cache or clicking "Reset" in the settings.

To deliver a reliable and improving experience, we use the following privacy-respecting third-party services:

• PostHog (Analytics): Helps us understand gameplay patterns (e.g., "Is Puzzle #4 too difficult?"). Configured in no-cookie mode with IP anonymization. No personal data is collected.
• Vercel Analytics (Performance): Monitors page load speeds and performance metrics to ensure the game runs smoothly. No cookies, no personal identifiers.
• Sentry (Error Monitoring): Captures technical errors and crashes to help us fix bugs. Does not collect personally identifiable information. Session replays (when errors occur) are anonymized and help us diagnose issues like the cloud save problems on specific devices.
• Upstash Redis (Cloud Saves & Leaderboards): Stores your optional cloud save data (game state and statistics) under a random Save ID. If you set a nickname, also stores your leaderboard scores and group memberships. No account required, no personal data attached. Saves expire after 1 year of inactivity.

All services are configured to minimize data collection and respect your privacy. No tracking cookies are used, and no data is sold to third parties.