Since 2001 · Unix and operations
Linux, FreeBSD, OpenBSD, NetBSD, Solaris/SmartOS and macOS.
A technical progression across 25 years. Tools changed; production responsibility and security remained constant.
Linux, FreeBSD, OpenBSD, NetBSD, Solaris/SmartOS and macOS.
Early hosting and housing infrastructure. Own racks since 2005; today a Boutique Private Cloud for 2342 products and selected project clients, not public hosting or housing.
One of the early Rails developers in Germany. Moved to Scala when Ruby no longer delivered the required performance.
One of the early iPhone developers in Germany.
Scala, Liftweb and distributed systems. Liftweb committer since January 2012. Maintained and adapted a fork of Foursquare's Rogue MongoDB DSL for Liftweb projects, and extended Slashem with write support.
Rebuilt and operated Kleinanzeigen.de end to end in Go on FreeBSD.
Kubernetes belongs to later platform and cloud projects. It was not part of the Kleinanzeigen platform.
Elixir for long-lived, fault-tolerant systems; in parallel, development of AI and ML systems.
Primary focus on production LLM systems and agentic workflows, with little classical ML work.
Go for CLI tools, Rust for libraries and small servers; since 2025 Swift apps and server-side Swift/Vapor through 2342.
AI security engineering and autonomous security research bring platform operations, offensive security and agentic systems together.
Accepted contribution for Alpine detection and apk support in CFEngine.
Accepted contribution: HandleContext for internally rewritten HTTP requests.
A project of my own with accepted contributions from other developers, including in 2017 and 2018. Further work dating from 2009 is classified and linked to original sources in the open-source index.
Application development and operations still belong together: traceable deployments, clear ownership and recovery plans. Existing platform teams can engage for architecture and implementation work; recurring incidents call for a focused SRE review.