Privacy

What is stored

• Your light or dark theme choice, in your browser’s local storage, so the site looks the same next time.

• Which rules you last chose, Standard or Relaxed, in your browser’s IndexedDB, so the next game starts with them.

• The game you are playing (the puzzle, your entries and notes, your time), in your browser’s IndexedDB, so you can continue it later. It is removed when you finish the game, and starting a new game replaces it. The daily puzzle, and a board opened from a shared link, are each kept the same way in a place of their own, so playing one does not replace a game of another kind.

• A record of each game you finish (the puzzle, its difficulty, your time, the hints you used and your mistakes, and the date if it was the daily puzzle), and of each game you leave unfinished and replace, in your browser’s IndexedDB (a won game is also held in local storage for a moment, until IndexedDB has it). Your finished-game statistics are worked out from these records and are kept on this device only.

• A copy of the site’s own pages and program files, and of the last 20 boards you opened from a link, in your browser’s cache storage, so the game opens without a connection. This cache holds no account session, saved games or personal information, and is replaced when the site is updated.

Each game on the site keeps its own saved game, rules and records, under its own name, so one game’s data never mixes with another’s. Clearing this site’s data in your browser settings removes its local copies. Synced copies remain with Supabase until you delete your account.

A board link you share holds only the puzzle’s starting numbers. A link to a daily puzzle holds only its date.

Account and sync

• When you sign in by email, your email address is used to send sign-in links and identify your account.

• After you accept the upload and sync prompt, Supabase processes and stores your saved games and finished-game records in the eu-central-1 region. The same account can sync them on devices where you sign in and accept the prompt.

• Your account and synced data are kept until you delete your account. To delete them, open /account, sign in, choose Delete account, and type your signed-in email address. Games and records stored in this browser stay on this device after deletion.

• An account data export is not available.

Analytics

We use Vercel Web Analytics to measure visits and page views. It does not use cookies. Vercel processes this data to show us aggregate traffic statistics.

Hosting

The site is hosted on Vercel. Like any web host, Vercel receives standard request information, such as your IP address, to deliver the pages.