Privacy

Operator

[To be completed: portal operator, address and contact e-mail]

What we store

We store only what the portal needs to sign you in and track your progress:

• the e-mail address you sign in with and to which we send verification and password reset links
• your password only as a one-way hash (scrypt with a random salt); we never store or see the password itself
• your display name, if you set one in your profile
• the solutions you submit: chosen options, numbers, the text of open answers and code, with the grading result and the time of submission
• your messages to Sensei, the task chat, and its replies (see below)
• points, badges and progress in lessons
• sign in data (a session), so you do not have to enter your password on every visit
• records of sign in attempts and sent links with the IP address, kept for at most 24 hours, to protect against password guessing and abuse

Why we need it

To sign you in and protect your account, to grade tasks, to show your progress and for the leaderboard. The leaderboard shows your display name or, if you have none, a shortened form of your e-mail.

Legal basis for processing: [To be completed: legal basis]

Who we share data with

The portal uses these service providers:

• Vercel: hosting (servers in the Frankfurt region)
• Neon: database (Frankfurt region)
• Google (Gmail): sending the e-mail with your verification or password reset link
• OpenAI: automatic grading of open answers. Only the task, the grading criteria and the text of your answer are sent, never your e-mail or name. So do not put personal data in your answers.
• OpenAI: replies of Sensei, the task chat (see below).
• jsDelivr: your browser downloads Python (Pyodide) from this network for code tasks. Your code runs only in your browser.

Sensei, the task chat

We store the messages you write to Sensei together with its replies, the time and whether the message was about the task. We also store the usage and cost of model calls so the portal stays within its monthly budget.

The lecturer (the operator of the portal) can read the conversations in the administration, even after you start a new conversation. They help improve the tasks and check that Sensei answers correctly.

To generate a reply we send OpenAI your message, the latest messages of the conversation, the task, the hints you opened and your last answer or code, never your e-mail or name. So do not put personal data in the chat.

Cookies

We only use cookies that are strictly necessary for signing in, for finishing a registration in the same browser and for protecting forms. We use no analytics or advertising cookies and do not track you across websites.

How long we keep data

[To be completed: retention period]

Your rights

You can ask for access to your data, its correction or deletion of your whole account. Write to [To be completed: contact e-mail].