Privacy policy
Last updated 25 October 2026
This explains what happens to your data when you use this site and buy One Screen at a Time. The short version: I keep almost nothing, there is no tracking and no advertising, and I never sell your data. Questions or requests: the contact address (to be added).
Who is responsible
Andrzej Stacherski runs this site. For the payment itself, Lemon Squeezy is the seller and handles your payment data under its own privacy policy.
What is collected, and why
| Data | Why | Who holds it |
|---|---|---|
| Name, email, billing details and payment data | To take your payment and issue a receipt | Lemon Squeezy. I see your email address and order details, not your card number. |
| Email address | To send your sign-in link, and to check that an address has bought the book | Resend sends the email. Lemon Squeezy confirms the purchase. I do not keep a mailing list or a database of buyers. |
| A sign-in cookie | To keep you signed in for 30 days | Your own browser |
| Theme choice and app progress (votes, seen facts) | To remember your light or dark choice and where you were in the demo app | Your own browser only (local storage). It never reaches a server. |
| Technical logs (IP address, browser, pages requested) | To run the site and keep it secure | Netlify, which hosts the site, for a limited time |
Cookies and tracking
The only cookie is the sign-in cookie. It is needed for the book to work, so it is not optional and there is no cookie banner. This site has no analytics, no advertising and no third-party tracking scripts. The sign-in cookie is marked secure and cannot be read by page scripts.
Who else sees your data
Only the services above: Lemon Squeezy (payments and purchase check), Resend (sign-in emails) and Netlify (hosting). They process data to provide their service to me and may do so outside your country, under their own safeguards. I do not sell your data or share it for marketing.
How long it is kept
I keep no buyer database. Lemon Squeezy keeps order records for as long as the law requires for tax and accounting. Resend and Netlify keep logs for a limited time under their own policies. Local storage and cookies stay on your device until you clear them or they expire.
Your rights
You can ask to see, correct or delete the personal data I hold about you, object to how it is used, or complain to your data protection authority. In Poland that is the UODO. Because most of your data sits with Lemon Squeezy, requests about payment records may need to go there as well, and I will help you do that.
Changes
If this policy changes, the date above changes with it.