Privacy
We keep as little about you as the product can work with, and we sell none of it. This page says exactly what we hold, why we hold it, and how to make us delete it.
Last updated 28 August 2026. Polygonjs is run by Guillaume Fradin, who is the data controller. Write to gui@polygonjs.com about anything on this page.
What we hold, and why
Your account
Your email address, your username, and your password stored as a hash we cannot reverse. This is what an account is. We need it to sign you in, to send you a password reset, and to tell you about your licence.
Signing in
Each time you sign in we record the IP address and the browser you signed in from, attached to that one session. It is there so we can answer you if you ever ask whether somebody else has been in your account. Only we can see it. Signing out deletes the record.
Your licence and the machines you activate it on
Your licence keys, and for every machine you activate, an identifier derived from that machine plus the name the operating system gives it. A licence has a fixed number of seats, and this is how we count them. It is also how you can move a seat off a machine you no longer own.
Your scenes
Scenes you save are yours. They are public by default, and you can mark any of them private from its edit page. A private scene is visible to you and to site administrators, and to nobody else. We read the contents of a private scene only if you ask us to, for support.
Paying
Payments run through Stripe. Your card details are entered on Stripe's own form and never reach our servers. We store the customer identifier Stripe gives us, so a payment can be matched to your account, and any note we write while helping you with an order.
The newsletter
Your email address, the date you confirmed it, and, if you arrived through a campaign link, which link that was. You are only added after you confirm by email. Every letter carries an unsubscribe link, and using it stops the mail immediately.
Crash reports
When the desktop app crashes, if you restart it you have the opportunity to send us a crash report. It carries no IP address and no account identifier, and it reaches an email address only if you type one in so we can reply. Reports are deleted after six months.
Measuring the site
We use Plausible, which sets no cookies and builds no profile of you. Your IP address is sent to it so it can work out a country and count you once for the day. Plausible discards the address rather than storing it, and we never see it in our analytics. Errors in the web editor are reported to Sentry from your browser so we can fix them.
Keeping the service up and unabused
Requests to our servers are logged, including the IP address they came from. We use those addresses to rate-limit, to block spam and automated signups, and to investigate abuse of the service, which includes copies of our software redistributed without a licence. Cloudflare Turnstile receives the address of anyone submitting a form so it can tell a person from a bot. We do not use any of this to build a profile of you or to advertise.
Why we are allowed to
Your account, your licence, your scenes and your payments are the contract between us. We cannot run any of it without them. The newsletter runs on your consent, which you can withdraw at any time. Sign-in records, logging, rate limiting and abuse investigation rest on our legitimate interest in keeping the service working and paid for, balanced against how little each one reveals.
Who else touches it
Each of these gets only what its job needs, and none of them may use it for anything else: Hetzner hosts our servers and database, in Falkenstein in Germany, Resend sends our email, Stripe takes payments, Cloudflare sits in front of the site and screens forms, Plausible measures traffic, Sentry receives editor errors, and Basecamp carries our internal notifications. Your account, your scenes and your licence therefore live in the European Union. Some of the processors above are outside it and operate under the standard contractual clauses.
How long we keep it
Account, licence and scene data lives for as long as your account does, and goes when you ask us to close it. Crash reports go after six months. Newsletter records go when you unsubscribe, except a note that the address unsubscribed, which we keep so we do not mail you again by accident. Server logs are capped in size and rotate away on their own. We keep no archive of them and we ship them nowhere else.
Cookies
We keep two cookies. One keeps you signed in. One lets the web editor fetch the engine it runs on. There is no advertising cookie and no tracking cookie on this site, which is why you are not reading this through a consent banner.
What you can ask for
You can ask for a copy of everything we hold about you, ask us to correct it, ask us to delete it, or object to a use of it. Write to gui@polygonjs.com and we will answer within a month. If you are in the European Union or the United Kingdom and you think we have handled this badly, you can complain to your national data protection authority.
Children
Polygonjs is made to be learned from, and children are welcome to use it. You do not need an account to open the web editor, build a scene and run it, so a child can use the tool without giving us anything at all.
An account and the newsletter are different, because both mean handing us an email address. If you are under sixteen, ask a parent or guardian before you create an account or subscribe, and let them do it for you if they would rather. We do not knowingly hold data about a child who has not asked. Write to gui@polygonjs.com if we have, and we will delete it.
Changes
This page carries the date it last changed, at the top. We add to it when something new starts collecting data. We do not quietly take things away.