Privacy

Version 0.2 · public preview · last updated 2026-07-11

The short version

Using this site without an account collects no personal data at all. No cookies, no analytics, no trackers, no third-party scripts. Signing in (optional, for cross-device sync) adds your email address and your learning progress to our database — nothing more.

Where your progress lives

By default, your lessons, XP, streaks, badges, and flashcard schedule are stored in your browser's local storage, on your device. We can't see them. Clearing your browser data deletes them; that is entirely in your hands. "Make available offline" stores lesson copies in your browser's cache the same way.

Accounts and sign-in (optional)

Signing in — via Google, GitHub, or an emailed sign-in link — lets your progress follow you across devices. Nothing about this is required to use the site.

If you sign in, we store: your email address, your display name (if you choose to set one), and your learning progress (lessons completed, XP/coin events, streak data). Your existing local progress merges in automatically the first time you sign in; nothing is lost or overwritten.

We don't store passwords — sign-in works entirely through your chosen provider (Google/GitHub) or a one-time emailed link, so there's no password of ours to leak. Your data is protected by database-level row-level security: only you (and, for support purposes, project administrators) can read your account's data — no one else, including other signed-in learners, can see it. Progress can only be written through a single, restricted server-side function; there is no direct write path into your XP or progress records.

We never sell your data or share it with advertisers, and there are no ad networks or third-party trackers on this site. Want your data exported or deleted? Open an issue on the project repository (see Contact below) and we'll handle it directly.

Hosting

The site is served by a content delivery network, which processes IP addresses transiently to deliver pages and protect against abuse, as all web hosting does. We run no server-side logging of our own beyond what's described above.

Contact

Questions or concerns: open an issue on the project repository — everything about this project happens in the open.