GDPR

Privacy policy

This is an English translation of the site's German Datenschutzerklärung, provided for accessibility. The German version is the legally binding one under GDPR and German data-protection law.

1. Controller

Michael Kupermann, Luegallee 118, 40545 Düsseldorf, Germany. Email: michael@kupermann.com.

2. Collection and storage of data on visiting this site

When this site is accessed, the web server in use (nginx) logs the following data in server log files:

• IP address of the accessing device
• Date and time of the access
• Requested URL, HTTP status, amount of data transferred
• User-agent (browser/operating system) and referrer

The collection serves the technical operation of the site and the defence against attacks. The legal basis is Art. 6 (1) (f) GDPR (legitimate interest). Log files are automatically deleted after a maximum of 14 days.

3. Cookies and tracking

This site sets no cookies, uses no analytics tracking (no Google Analytics, no Matomo, no Plausible), no fingerprinting, and loads no external fonts or CDNs. All resources are served from the site's own server.

4. Encryption (TLS)

The site is served exclusively via HTTPS (TLS 1.2/1.3). The certificate is obtained from Let's Encrypt and renewed automatically.

5. Contact by email

If you contact me by email, I process your details (email address, message content) in order to respond to your enquiry. The legal basis is Art. 6 (1) (b) or (f) GDPR. The data are deleted as soon as they are no longer needed for the purpose — at the latest when statutory retention periods expire.

6. Hosting

The server is operated in Germany by Hetzner Online GmbH. A data-processing agreement pursuant to Art. 28 GDPR is in place.

7. Google Search Console (domain verification)

This domain is verified with Google Search Console. The verification consists of a passive google-site-verification meta tag in the HTML head. The tag sets no cookies, loads no external resources, and transmits no data to Google when a visitor opens the page. Search Console provides the site operator only with aggregated statistics (for example, search queries that returned this site), based on data Google already collects when indexing the web. Provider: Google Ireland Limited, Gordon House, Barrow Street, Dublin 4, Ireland.

8. External links

This site contains links to external sites (among others GitHub, LinkedIn). When you follow such links, the respective privacy policies of those providers apply.

9. Your rights

You have the following rights in relation to the personal data concerning you:

• Right of access (Art. 15 GDPR)
• Right to rectification (Art. 16 GDPR)
• Right to erasure (Art. 17 GDPR)
• Right to restriction of processing (Art. 18 GDPR)
• Right to data portability (Art. 20 GDPR)
• Right to object (Art. 21 GDPR)

To exercise these rights, an informal email to the address above is sufficient.

10. Right to lodge a complaint

You have the right to lodge a complaint with a data-protection supervisory authority. The competent authority is the State Commissioner for Data Protection and Freedom of Information of North Rhine-Westphalia (LDI NRW).

11. Status

This privacy policy is dated April 2026.