GDPR · German Federal Data Protection Act · TTDSG

Privacy Policy

This is an English summary for the convenience of non-German readers. The legally binding version is the German Datenschutzerklärung.

1. Data controller

The controller responsible for data processing on this website is:
Kai Hackbarth · Hagener Straße 67 · 58285 Gevelsberg · Germany
kai@kaihackbarth.com

2. Data collection on plain visits

When you simply browse the site, only the personal data your browser sends to the server is collected (server log files): IP address, date and time of the request, transferred volume, requesting provider, user agent. This data is used solely to ensure smooth operation of the site (Art. 6 (1) (f) GDPR; legitimate interest in security and functionality).

3. Hosting

This site is hosted by Vercel Inc., 340 S Lemon Ave #4133, Walnut, CA 91789, USA, via their global content delivery network with edge servers in the EU. Vercel processes access data (server log files, IP address, technical connection information) on our behalf (data processing agreement under Art. 28 GDPR).

Third-country transfer: A transfer to the US takes place. This is based on Standard Contractual Clauses under Art. 46 (2) (c) GDPR; Vercel is additionally self-certified under the EU-US Data Privacy Framework. Details: vercel.com/legal/privacy-policy.

Audience measurement (Vercel Web Analytics): This site uses Vercel Web Analytics, a cookieless analytics service by Vercel. Only aggregated, anonymised usage data is collected (pages viewed, approximate country-level location, device type, referrer). No cookies are set, no IP addresses are stored persistently, and no cross-device profiles are built; individual visitors cannot be identified. Legal basis: Art. 6 (1) (f) GDPR (legitimate interest in privacy-preserving audience measurement). No consent under § 25 TDDDG is required, as no information is accessed on or stored in your device.

4. Web fonts (Bunny Fonts)

This site loads web fonts (DM Serif Display, Outfit, JetBrains Mono) via Bunny Fonts, an EU-hosted font service operated by BunnyWay d.o.o., Cesta komandanta Staneta 4A, 1215 Medvode, Slovenia. According to its provider, Bunny Fonts does not store IP addresses, set cookies, or transfer personal data to third parties. Legal basis: Art. 6 (1) (f) GDPR (legitimate interest in consistent, accessible presentation of the site). Details: bunny.net/privacy.

5. External libraries (CDN)

This site loads JavaScript libraries (React, Babel, Lucide icons) via the content delivery network unpkg.com, operated by Cloudflare, Inc., 101 Townsend St, San Francisco, CA 94107, USA. Your IP address is transmitted when these files load. Legal basis: Art. 6 (1) (f) GDPR (legitimate interest in a functioning site with performant delivery of static assets). Third-country transfer to the US is covered by Standard Contractual Clauses.

6. Embedded videos (YouTube)

In the "Speaking" section, a thumbnail of a YouTube video is shown. Only after a deliberate click on the thumbnail does the actual YouTube player load (a so-called click-to-load pattern). We use the youtube-nocookie.com variant (YouTube's enhanced privacy mode), which transmits less data to Google than the standard embed.

Only after you click the thumbnail is data transferred to Google Ireland Limited, Gordon House, Barrow Street, Dublin 4, Ireland — or to Google LLC in the US — including your IP address and possibly other browser-side identifiers. Legal basis for the data transfer that follows the click is Art. 6 (1) (a) GDPR (consent through the active interaction). Details: policies.google.com/privacy.

7. Contact

If you contact us by email, your information is stored to process the enquiry and any follow-up questions. Legal basis is Art. 6 (1) (b) GDPR (pre-contractual measures) or Art. 6 (1) (f) GDPR (legitimate interest in efficient processing).

8. "Signal" newsletter

For the monthly newsletter "Signal" we use the US-based provider beehiiv, Inc., 228 Park Ave S, PMB 29976, New York, NY 10003, USA. When you sign up, your email address and technical connection data (IP address, timestamp) are transmitted to beehiiv and stored there.

Double opt-in: After signing up, you receive a confirmation email. Only after you click the confirmation link are you added to the distribution list. This ensures only the holder of the email address receives the newsletter. Sign-up and confirmation timestamps are logged as proof of consent.

Measurement: beehiiv records by default whether and when you open the newsletter emails and which links you click. We use this information to improve content and send times for the entire readership; no analysis on an individual level takes place.

Legal basis: Art. 6 (1) (a) GDPR (your consent through the double opt-in confirmation). You can withdraw this consent at any time — through the unsubscribe link in every newsletter email or by message to kai@kaihackbarth.com. The withdrawal does not affect the lawfulness of processing carried out before that point.

Third-country transfer: beehiiv processes data in the US. The transfer is based on Standard Contractual Clauses under Art. 46 (2) (c) GDPR. Details: beehiiv.com/privacy.

9. Your rights

You have the following rights with respect to your personal data:

The competent supervisory authority is the State Commissioner for Data Protection and Freedom of Information of North Rhine-Westphalia (Landesbeauftragte für Datenschutz und Informationsfreiheit NRW), Postfach 20 04 44, 40102 Düsseldorf, Germany.

10. Cookies

This site sets no first-party tracking or marketing cookies. Third parties (see above) may set cookies once you actively use their services — in particular YouTube, when you click the thumbnail of a video. Before that click, no YouTube cookies are set. Strictly necessary cookies are used only server-side, where required for the operation of the site.

11. Currency of this policy

This privacy policy was last updated on 27 May 2026. We reserve the right to adapt it to applicable legal requirements as needed.

← Back to home