Privacy policy
Last updated: October 18, 2026
Initial version. It may change after a legal review; if anything important changes, we will let you know.
Who is responsible
Cuby (gocuby.com) is responsible for the data processed in Cuby. For any question, write to hola@gocuby.com.
What we keep
Your email and, if you add it, your name; your language and time zone; what you tell us in the welcome (your role and goal); your progress, attempts, diagrams and answers.
To stop abuse, the server uses your IP to limit requests. It keeps it in memory only: it never writes it to disk or the database, and it is gone when the server restarts.
What we use it for
To provide the service: grading your submissions, keeping your progress, generating AI feedback, sending sign-in emails and answering you if you write to us. Also, in aggregate, to understand how Cuby is used and improve it.
Who we share it with
Polar processes payments and keeps billing data.
Anthropic generates AI feedback: it receives the case, your diagram and your answers, never your email.
Amazon SES sends the sign-in emails.
Google Fonts serves the pages' typefaces, so it receives your IP when they load.
PostHog, when enabled, receives usage events (for example, that you started a challenge) with a pseudonymous identifier, without your email.
We do not sell your data or share it for advertising.
How long we keep it
As long as you have your account. If you close it, we delete your data, except what the law requires us to keep (for example billing, which Polar keeps).
Your rights
You can ask to access, correct, export or delete your data by writing to hola@gocuby.com. We answer within 30 days.
Security
Everything travels encrypted (HTTPS). Sign-in links and sessions are stored as hashes, so not even we can use them.
Changes
If we change this policy in an important way, we tell you by email or in the app.
Contact
Write to us at hola@gocuby.com.