Privacy Policy

I am no fan of complex legal texts — here is the TL;DR

What gets stored:

• Aggregated, anonymous usage statistics (self-hosted analytics — no cookies, no stored IP addresses)
• Short-lived technical server logs (IP address, user agent, timestamp) for security and operations
• Your email address — only if you subscribe to the newsletter (kept until you unsubscribe) or write me an email

What does NOT get stored:

• No cookies, no fingerprinting, no cross-site profiles
• No third-party trackers, ad networks, or social-media pixels
• Nothing is ever sold or shared — no data leaves my own servers

Who is responsible

Responsible for this website and its data processing is the person named in the imprint. For any question about this policy or your data, contact hello@felixmertins.dev.

What this site does NOT do

• No cookies of any kind
• No third-party analytics (no Google, Meta, etc.)
• No advertising or remarketing pixels
• No social-media trackers
• No fingerprinting or cross-site tracking

For navigation comfort the site keeps your scroll position in your browser's sessionStorage. That value never leaves your device, contains no personal data, and is discarded when the tab closes.

Self-hosted analytics (Umami)

This site uses Umami, a privacy-friendly, open-source analytics tool, hosted on my own infrastructure. It collects aggregated, anonymous usage data: page views, referrer, browser, OS, device type, screen size, and the approximate country derived from the IP address — the IP address itself is not stored. Umami sets no cookies, builds no cross-site profiles, and shares no data with third parties; the data never leaves my server. Legal basis: Art. 6 (1) (f) GDPR (legitimate interest in understanding aggregate traffic to operate and improve the site). If you block the analytics script with a content blocker, the site works exactly the same — nothing is collected.

Newsletter (self-hosted listmonk)

If you subscribe to the newsletter, your email address is stored on my own listmonk server — no third-party mailing provider is involved. The subscription uses double opt-in: your address only becomes active once you confirm it via the email you receive. The address is used exclusively to send the newsletter; the emails contain no open or click tracking. Every issue contains an unsubscribe link — unsubscribing deactivates your address and it is subsequently deleted. Legal basis: Art. 6 (1) (a) GDPR (consent), revocable at any time.

Server logs

The web server briefly processes technical access data (IP address, user agent, requested URL, timestamp) to deliver the site and protect against abuse. These logs are not merged into user profiles and are rotated and deleted automatically after [X days]. Legal basis: Art. 6 (1) (f) GDPR (legitimate interest in operating a secure service).

Contact

If you email me at hello@felixmertins.dev, your message and address are stored only as long as needed to handle your request. You can encrypt your message with my PGP key.

External links & discussion lists

Outbound links (GitHub, IETF, ORCID, Mastodon, Bluesky, Matrix, LinkedIn, etc.) are governed by the respective providers' privacy policies; following such a link transmits standard request headers to that third party. Some projects and posts link to mailing/discussion lists — joining one of those lists is governed by the terms and privacy practices of the respective list service.

Your rights

Under the GDPR you have the right to information, correction, deletion, restriction of processing, data portability, and objection. Contact me at hello@felixmertins.dev. You may also lodge a complaint with a data protection supervisory authority.

Changes to this policy

This policy is updated whenever the site's actual data processing changes (for example, when a new feature is introduced). The current version is always the one published on this page.