Privacy

Your email address, but only if you sign in with one. Bayana has no passwords: you type an address, it sends a one-time link, and clicking it signs you in. The address is kept so it can recognise you next time. The link itself is stored only as a hash, and it stops working once used or expired.

Your study progress. Which words and grammar points you have seen, how you rated each one, when each is next due, and your chosen JLPT level. This is the app: without it there is no spaced repetition.

Nothing else. No name, no age, no location, no contacts, no payment details. Bayana never asks for them and has nowhere to put them.

The demo needs no email at all. Starting one creates an anonymous account and puts a signed cookie in your browser, and that cookie is the only key to it. There is no way to reach demo progress without it — not for you, and not for me.

A demo cookie stops working 7 days after it is issued, and the account behind it is deleted within 14 days of being created, by a job that runs daily whether or not anybody visits. Clearing your cookies makes the data unreachable immediately; deletion then happens on the same schedule.

There are no analytics, no tracking pixels, and no third-party scripts of any kind. Not a lighter alternative to Google Analytics — none at all. Bayana's content security policy permits no external origin, so the browser is not allowed to load anything from anywhere else even by accident.

The only cookies are the two that make signing in work: a session cookie for email accounts, or the signed demo cookie. Both are strictly necessary, neither follows you anywhere, and there is nothing here for a consent banner to ask about.

Three companies, each doing one job:

Resend delivers your sign-in email, so it necessarily handles your address. It sees nothing else. Railway hosts the app and the database it runs on, so your data physically sits on their infrastructure.

Anthropic wrote the example sentences, and this one is worth being precise about: nothing you do in the app is ever sent to an AI model. The sentences were generated once, ahead of time, from the vocabulary list alone, and stored in the database. Studying a card reads a sentence that already exists. There is no request to an AI service while you use Bayana.

Demo accounts: deleted within 14 days, as above.

Email accounts: kept until you ask for them to be deleted, because study progress is only worth having if it survives. Ask and it goes — the account, the review history, all of it, permanently, and there is no separate backup copy to hunt down afterwards.

If what Bayana collects changes, this page changes with it, and the date at the top moves. The whole history of this file is public in the repository, so you can see exactly what changed and when.