Privacy

Plain words

We collect as little as we can, and this page says exactly what that is. If anything here is unclear, write to support@desmoswizard.com and we’ll answer like a person.

While you play

Your progress, the first name you give your city, your streak and your access code are saved in your browser’s local storage, on your device. They aren’t sent to us. Clearing your browser data removes your progress from that device. Your code keeps working. The graphing calculator is our own and runs in your browser: nothing loads from desmos.com, and what you type isn’t sent to Desmos.

“Save your city”

This is optional. If you type an email there, we send that address one message: a link that brings your city back on any device. The link holds your city, the first name you gave it and your device’s code, so keep it to yourself.

To send it, the address goes to our email provider, Resend, and nowhere else. We don’t keep it in a database, we don’t add it to a list, and we won’t send you anything else, no news and no offers, unless you ask us to. Our server log notes that a message went out, with the address mostly hidden (like m***@gmail.com), and our host keeps those logs only briefly.

When someone pays

Payments are handled by Stripe. We never see or store card numbers. From Stripe we receive the payer’s email (for the receipt and for resending a lost code), the amount, the card’s country and the access code tied to the payment. If you gave your city a first name, it goes on the receipt too.

Counting what works

To see where the course breaks or confuses people, we may count steps like “opened level 1”, “finished level 1” or “opened checkout”, using PostHog under a random id made on your device. No name, no email, no tracking across other sites, and nothing used for ads. Like every website, our host (Vercel) briefly keeps standard server logs, which include IP addresses, to keep the site running and safe.

18 and older

desmos wizard is only for people 18 and older and isn’t directed at children. We don’t knowingly collect personal information from anyone under 18. If you think someone under 18 gave us information, write to support@desmoswizard.com and we’ll delete it.

Who else touches the data

• Stripe, for payments and receipts.
• Vercel, which hosts the site.
• PostHog, for the anonymous counts above, only when it’s switched on.
• Resend, our email provider, only to send the “Save your city” link or a lost code.

Each one gets only what its job needs.

Your choices

You can ask for a copy of what we hold about you, or for it to be deleted, at support@desmoswizard.com. We’ll do it within 30 days, usually much sooner.