22 · Linux & Cybersecurity · Infrastructure · Entrepreneur
I'm fascinated by technology, infrastructure and the systems that power the digital world. My interests range from Linux, networking and cybersecurity to self-hosting, automation and software development.
I enjoy understanding how things work beneath the surface, connecting different technologies and building solutions from the ground up. Rather than relying on ready-made services and subscriptions, I prefer having control over my own infrastructure, experimenting with new technologies and developing tools that solve real-world problems.
I'm particularly interested in:
- Linux & Infrastructure – Linux systems, server administration, networking, Docker and self-hosted environments.
- Cybersecurity – System hardening, infrastructure security, vulnerabilities and secure architecture.
- Self-Hosting & Digital Sovereignty – Running my own services, controlling data and reducing dependency on third-party platforms.
- Software & Automation – Building practical software, integrating systems and automating repetitive processes.
- Entrepreneurship – Turning technical ideas into useful products, exploring business opportunities and building things independently.
invoicelite is self-hosted invoicing for German businesses, in a single Docker container. I built it because I did not want to pay a subscription for my own invoices or keep assembling them in Word, and the German e-invoicing mandate was going to end that anyway.
- XRechnung 3.0.2 and ZUGFeRD, validated against the official KoSIT validator
- The §19 and §13b tax regimes, recorded per document rather than globally
- GoBD: approved documents are locked, numbering stays gapless
- Income-surplus statement (EÜR) as PDF and CSV for the tax advisor
The interface and documents are German, because the software encodes German law.
License: Sustainable Use License, the same one n8n uses. Self-host and modify freely, including commercially. Source-available, not OSI open source.