Professional software development

Great software is created through continuous, iterative, test-driven improvement — with the people who build it, not over them.

I am a software and systems developer, DevOps and SRE expert, and consultant. Besides German and English, I'm especially fluent in Python. My current employers are mkk and SNTL-Publishing.

Instead of reading this page, feel free to talk to my AI agent. :)

Where I want to make an impact

Climate catastrophe

The climate catastrophe is the biggest problem that we as humanity have to solve. If your project contributes to that, please contact me!

Digital sovereignty

Technological independence is a strategic necessity — especially for Europe — as a counterweight to geopolitical uncertainties and dependencies on individual vendors and platforms. If you share this conviction, we should talk.

Open source

Free software and open standards are the practical foundation of technological independence. Open source enables something remarkable: shared foundations, real competition — coopetition in practice. I actively contribute to many open-source projects and therefore know where this approach is strong and where its limits lie. If you want to use free software strategically, I'm happy to help.

What I offer

Software

On the basis of free software, I've been developing and modernizing the frontends and backends of complex web- and desktop-based software systems since 1998. I'm convinced that quality is best achieved through an iterative process ("inspect & adapt") and test-driven development.

AI integration

Artificial intelligence is fundamentally changing software development — but not every use case makes sense. I know the strengths and weaknesses of current AI technologies and help teams capture the real benefits without taking on the downsides: from AI-assisted development in daily work to integrating language models into existing systems and automations.

DevOps & SRE

I run complex monoliths and service architectures as well as monitoring, backup, and load-balancing tools. I support operations in an automated and reproducible way on Linux — depending on requirements on bare metal, in virtual machines, or in containers.

Mentoring

For me, mentoring is the natural way to get to know people and help them grow — in day-to-day work, not in a seminar room. Pair programming for debugging, code reviews, targeted improvements to tooling: knowledge anchors sustainably in the team this way, instead of disappearing into individual heads. I have the patience to meet everyone where they stand.

Team development

Silos don't emerge from ill will — they're the default state when teams aren't deliberately connected. I build these connections from within: first earn trust, then jointly understand where local optimization blocks global goals, then propose structures that everyone can get behind — architecture forums, ADRs, shared standards. The goal: teams that work together because they want to, not because they have to.

Security

I grew up in the Chaos Computer Club — that shapes a view of software that asks: "What can go wrong here, and how?" Security isn't a separate discipline for me but a mindset: SQL injections, insecure configurations, or forgotten attack surfaces catch my attention in daily work — and become mentoring moments on the spot. That's how security awareness emerges organically within a team.

A reliable network of experts

A good network isn't a luxury — it's a tool. Grown over years from working together, open source, and a shared passion for good software: I know who to ask — and in practice, that has often saved days to weeks of work, prevented dead ends, or pointed straight to the better path.

What I can do

Currently learning: Machine Learning & Deep Neural Networks, Data Evaluation, Data Pipelines, Data Visualization, Go.

Best at: Python, Flask, SQLAlchemy, Alembic, Jinja, pytest, automated testing, unit tests, refactoring, CI/CD, infrastructure as code, reproducible infrastructure, Nix, NixOS, nix-darwin, Docker/containers/Kubernetes, Helm, API design, REST APIs, Nginx, Postgres, MySQL, SQLite, AI-assisted development, shell, Git.

Strong: Pyramid, Django, PyPy, ruff, black, uv, pre-commit, devenv, GitLab CI, GitHub Actions, Ansible, Terraform, Prometheus, Grafana, Loki, Icinga, CockroachDB, InfluxDB, Redis, Sealed Secrets, sops, 1Password CLI, cert-manager, LDAP, OpenID Connect, OAuth, HAProxy, Caddy, microservices, strace, Wireshark, Linux administration (Red Hat/CentOS, Debian, NixOS, Ubuntu), shell power tools (direnv, zoxide, fzf, bat, jq, yq, jless, …), Jupyter, LLM integration, Scrum/Agile development (Scrum Master, iterative and incremental, Lean Management), open source/free software, …

Long ago: NumPy, pandas, Tornado, Selenium/WebDriver/Playwright, Ruby, Capybara, Apache HTTPD, Objective-C, Cocoa, XCTest, Core Data, Xcode, C/C++, Java, Smalltalk, Jenkins, Matplotlib, Font Awesome, Bootstrap, CSS, Sass/SCSS, HTML5, JavaScript, R, TypeScript, JavaScript (Vue.js, jQuery, Backbone.js, Angular.js, D3.js, Bokeh, Jasmine, JSON Editor, Ember.js, SproutCore.js), CoffeeScript, Make, LESS, Autotools, Vagrant, Puppet, RabbitMQ, ZeroMQ, XML Schema, XPath, networks and P2P systems, concurrent programming, assembler, usability, Mercurial, Bazaar, SVN, CVS, ZODB, Zope, MongoDB, Eclipse, Trac, Bitten, SyncML, Bluetooth, RDF, ontologies, 3D modeling, Maya, Arduino, IBM Db2, Oracle Database, MSSQL Server, …

Work

mkk - Meine Krankenkasse

I work for mkk as a Solution Architect and Senior Developer in the areas of backends, system automation, DevOps, and Site Reliability Engineering — a role that has increasingly evolved into a cross-team tech lead. There I develop backend services and workflow engines in Python/Flask, run the infrastructure on Kubernetes (Helm, Prometheus, Grafana, Loki), and drive the migration from legacy systems and click-ops toward GitOps and infrastructure as code — including in the context of KRITIS certification, where resilience and operational capability are paramount. A particular focus is the introduction of AI across the entire organization: from evaluating and hosting our own language models, to developing AI-powered document classification, to training a broad group of multipliers from the business departments. As a technical coach and driver of the architecture forum, I work to establish cross-team standards and strengthen technical excellence across all teams through mentoring, code reviews, and Architecture Decision Records.

SNTL-Publishing

For SNTL-Publishing I work as a Full-Stack Developer, DevOps and SRE expert, and Software Architect. My focus is the predictive learning analytics tool yeepa, which I significantly co-developed. yeepa enables live learning games against other people and evaluates the results using Item Response Theory (Rasch model) — the same method underlying the PISA studies — to deliver quantitatively robust comparisons of knowledge levels and training effectiveness. The architecture comprises a Tornado-based async backend for real-time game logic, a Pyramid application for administration and evaluation, and background jobs for statistical computations. Beyond that, I operate the entire server infrastructure (~30 servers) fully via Ansible — from yeepa to CMS systems with hot standby, mail, Nextcloud, and monitoring. In addition, I consult and train SNTL's clients — from Nginx coaching to container deployments to setting up complete production environments.