Privacy Policy

1. Who is responsible

The controller is:

Email: support@node-l.com. Contact form: node-l.com/contact.

2. Visiting the website

• Node-L runs on servers rented from Hetzner Online GmbH, Germany, which processes the data on our behalf.
• When you open a page, your browser sends technical data (IP address, time, the page requested, browser type). Our web server and application use it to deliver the page, keep the service secure and find errors (legal basis: our legitimate interest in a working and secure service, Art. 6(1)(f) GDPR).
• To stop abuse, some actions (sign-up, sign-in help, the contact form and others) are counted per IP address or per account for a short time. Each counter is deleted when its time window has ended.
• We use no analytics or advertising tools, no tracking pixels and no third-party cookies. Fonts are served from our own server.

3. Your account

• When you sign up we process your email address, username, password (stored only as a one-way hash), the roles and languages you choose, and, if you give them, your first and last name. We send a link to confirm your address. Legal basis: the contract (Art. 6(1)(b) GDPR).
• Your public profile shows your username and the public nodes and courses you published. Your first and last name appear there only if you switch them on, and a short bio only if you write one. Private courses are never shown on a public profile.
• You can change your profile, your password and your email address in the settings. A change of email address is confirmed by a link to the new address; the previous address gets a link to undo it for 7 days.

4. Learning and teaching

• We store the nodes and courses you create, your answers, scores, progress and play history, your ratings, stars, saved nodes and dictionary entries, the essays you submit and the feedback on them. Legal basis: the contract (Art. 6(1)(b) GDPR).
• A teacher sees, under your username, the results of the nodes in courses you have joined and confirmed, including your essays and their feedback. A School sees counts and averages for the shared nodes used in its teachers' courses, never students' names, and an average only over at least three students.
• Comparisons with other students use anonymous averages, never names.
• Error reports you send with the Report an error button while you play a node go to the node's author and to us.

5. AI features

• When you use an AI feature, the text it needs is sent to Anthropic (Anthropic, PBC, USA), which runs the language model and returns the answer. Depending on the feature this is the exercise content, your answer, your question or your essay. We do not send your name, email address or username.
• Explanations and Ask AI answers are kept in a cache so that the same question is not sent twice. The cache holds the exercise and the answer text, not who asked; each entry is deleted 12 months after it was made, or earlier when its node is deleted.
• When an explanation suggests that your answer may also be right, a note with your answer goes to the node's author so that they can check the answer key. The author does not see who gave the answer. Notes are deleted after 12 months at the latest, and 30 days after the exercise was changed.
• AI grading of essays: the essay and the task are sent to Anthropic; the grade and the feedback are stored with the essay. An AI grade is feedback for learning. No decision with legal effect is made about you by automated means alone.
• Legal basis: the contract (Art. 6(1)(b) GDPR). Anthropic is located outside the EU; see section 11.

6. Text-to-speech

When a teacher generates a recording for a Listening or essay node, the text of the recording is sent to Google Cloud Text-to-Speech (Google), which returns the audio. The text is the teacher's exercise content. The recording is stored on our server. Legal basis: the contract (Art. 6(1)(b) GDPR). Google is located outside the EU; see section 11.

7. Emails

• We send emails through Brevo (Sendinblue SAS, France), which processes your address and the email on our behalf.
• We send the emails the service needs: confirmations, password and email-address changes, course and School invitations and requests, AI allowance notices for teachers, and, after the payments build, the emails about your plan. Course update emails can be switched off in the settings. We send no newsletters or advertising.
• We keep a log of sent emails. The text of a logged email is deleted after 30 days, the log entry (address, subject, date and status) after 12 months.
• Legal basis: the contract (Art. 6(1)(b) GDPR); for course update emails our legitimate interest in informing course members (Art. 6(1)(f) GDPR).

8. Contacting us and other users

• Messages through the contact form (your name, email address and message) are stored and forwarded to our mailbox, so that we can answer. Legal basis: our legitimate interest in answering you (Art. 6(1)(f) GDPR), or steps before or under a contract (Art. 6(1)(b) GDPR).
• You can ask another user to get in touch through the Connect button on their profile. They receive your request by email, with the name you show (or your username) and your message, never your email address. They decide how to answer: if they agree to share their email address, we send it to you; they can also decline, or give you another way to reach them. We do not store the request itself, only who asked whom and when, to limit misuse; the emails are in the sent-email log (section 7).

9. Payments (after the payments build)

• Paid plans are paid on the checkout page of Stripe (Stripe Payments Europe, Limited, Ireland). Stripe processes the payment details, the billing address and, if you give one, a VAT identification number. Your card details never reach us.
• We receive from Stripe what we need to run your plan: a customer reference, the plan, the billing cycle, the status of the subscription and its dates. Stripe sends receipts and invoices.
• Legal basis: the contract (Art. 6(1)(b) GDPR) and our duties under tax and commercial law (Art. 6(1)(c) GDPR).

10. Error recording

If a page crashes, your browser sends us a technical report: the error type, a few lines of the program's call stack and the page address. Server errors are recorded the same way. Reports contain no error messages and no account names; an error group is deleted 30 days after it was last seen. Legal basis: our legitimate interest in a working service (Art. 6(1)(f) GDPR). No outside error-tracking service is used.

11. Recipients and transfers outside the EU

• Hetzner Online GmbH, Germany: hosting (processor).
• Brevo (Sendinblue SAS), France: sending emails (processor).
• Anthropic, PBC, USA: AI features (processor).
• Google (Google Cloud Text-to-Speech): recordings (processor).
• Stripe: payments, after the payments build.
• Authorities, where the law obliges us.

For Anthropic and Google, data is transferred to the USA. The transfer is based on the EU standard contractual clauses in the providers' data processing terms or, where the recipient is certified, on the EU-U.S. Data Privacy Framework.

12. Cookies and browser storage

Node-L sets only the cookies the sign-in needs, so no consent is asked for (§ 25(2) of the German TDDDG):

• the session cookie, which keeps you signed in (up to 30 days, or until you sign out);
• a security token against forged requests (until you close the browser);
• the page to return to after signing in (until you close the browser).

Node-L also keeps a few settings in your browser's local storage and IndexedDB, which never leave your device unless you save them: which view you use (student or teacher), unsaved node drafts so that you can recover them, the hints you have already seen, the language you chose for AI help, and the state of an essay grading in progress. A node draft that your browser sends to our server for recovery is described in section 13. You can delete them in your browser's settings.

13. How long we keep data

• Account data: until the account is deleted.
• Sent-email log: the text 30 days, the entry 12 months.
• Error groups: 30 days after they were last seen.
• Answer-key notes: up to 12 months.
• Node drafts saved on our server for recovery: 21 days after their last update.
• Cached AI explanations and answers: 12 months after they were made.
• Abuse counters: until their time window ends.
• Billing records: as long as German tax and commercial law requires (§ 147 of the Fiscal Code and § 257 of the Commercial Code), up to ten years.

14. Your rights

• You have the right to access your data (Art. 15 GDPR), to have it corrected (Art. 16), deleted (Art. 17) or restricted (Art. 18), to receive it in a portable format (Art. 20), and to object to processing based on our legitimate interest (Art. 21).
• To use a right, write to us from the email address of your account (support@node-l.com or the contact form), so that we know the request is yours. We answer within one month.
• Many changes you can make yourself in the settings. Account deletion happens on request: write to us through the contact page from the email address of your account. Your account is then anonymised: your name, email address, profile and password are removed and you can no longer sign in. Nodes and courses you published stay available under an anonymous name, and results in other people's courses remain under that name, because other users depend on them.

15. Right to complain

You can complain to a data protection supervisory authority, in particular in the EU country where you live or work. The authority responsible for us is the Bavarian State Office for Data Protection Supervision (Bayerisches Landesamt für Datenschutzaufsicht), Promenade 18, 91522 Ansbach, Germany.

16. Changes to this policy

We update this policy when Node-L or the law changes. The date at the top shows the version. We tell account holders by email of changes that matter to them.