Privacy Policy

1. Who we are

This website and application (the “Service”) is operated as Tianxue (“we,” “us”). This policy explains what information we collect, how we use it, and the choices you have. For any privacy question or request, contact del.9x92c@aleeas.com.

2. Information we collect

• Account information. Your email address and a password. Passwords are handled by our authentication provider (Supabase) and stored only in hashed form — we never see or store your password in plain text.
• Profile information (optional). A first and last name and a home-language preference, if you choose to provide them.
• Learning activity. Your course enrollments, review schedule and history, self-ratings, answers and writing you submit in exercises, and internal estimates of your skill level used to adjust difficulty.
• Uploaded content. If you are a course creator, the documents, media, and links you upload or import to build course material, and content generated from them.
• Invitations. If a course creator invites you by email, we store that email address to connect you to the course when you sign up.
• Technical logs. Our infrastructure providers keep standard server logs (such as IP address, browser type, and timestamps) to operate and secure their services.

3. What we don’t do

• We do not sell your personal information.
• We do not show ads or share your data with advertisers.
• We use cookies necessary for authentication, security, and core functionality. We do not use advertising or analytics cookies.
• We do not collect payment information (the Service currently has no paid features).

We do not track your activity across third-party websites or allow third parties to use the Service for behavioral advertising. Because we do not engage in this tracking, browser Do Not Track or Global Privacy Control signals do not change how the Service operates.

4. How we use your information

We use the information above to:

• provide the Service — accounts, courses, exercises, and review scheduling;
• personalize your learning, such as scheduling reviews and adjusting exercise difficulty based on your past answers;
• send essential account emails, such as signup confirmation (sent by our authentication provider — we do not send marketing email);
• maintain the security and reliability of the Service; and
• respond when you contact us.

5. Service providers

We use a small number of infrastructure providers to run the Service. They process data on our behalf to provide their services:

• Supabase — authentication, database, and file storage. This is where account, profile, learning, and uploaded-content data lives.
• Vercel — hosting for the web application.
• Fly.io — background processing of uploaded and imported course material.
• Anthropic — AI generation of study materials. Anthropic receives course source content (for example, an uploaded document or transcript) together with our generation instructions. We do not intentionally include account or profile information, or answers and writing learners submit in the app, in these requests — but uploaded source material is sent as provided and may itself contain personal information.

These providers may store and process data in the United States and other locations where they operate.

6. Visibility within courses

Courses are run by course administrators. The administrators of a course you join can see your membership information and, within their course, your learning progress, review history, and the answers and writing you submit. Course materials published in a course are visible to the users enrolled in it.

7. Retention and deletion

We keep your information for as long as your account is active. You can update your profile information in the app at any time. To request deletion of your account and associated personal data, email del.9x92c@aleeas.com and we will delete it from our active systems within a reasonable time. Limited information may remain temporarily in backups and security logs, or be retained where we are legally required to keep it. Content you contributed to shared courses may be retained where needed for other users, with your identity removed where practical.

8. Security

We use reasonable technical measures to protect your information, including access controls and encrypted connections. No online service can guarantee perfect security, so please use a strong, unique password.

9. Children

The Service is for adults (18+) and is not directed to children. We do not knowingly collect personal information from anyone under 18. If you believe a minor has created an account, contact us and we will delete it.

10. Changes to this policy

We may update this policy from time to time. If we make material changes, we will update the effective date above and take reasonable steps to notify you, such as a notice in the Service.

11. Contact

For any question or request about your data, email del.9x92c@aleeas.com.