Work
A selection from more than 100 completed projects — from concept to production. The following three represent different roles: as an operator over years, as the lead for a concrete migration, and as a pure architect at enterprise scale.
Building and Operating a Blended Care Platform
Period: 2020–2023 · Role: CTO and Software Architect · Industry: Healthcare
Context
For three years, I designed, built, and kept in production a blended-care platform for psychological counseling in women's health. Unlike most projects on this list, I was responsible end-to-end here — from the first architecture decision through daily operations — with no handoff to another team after go-live.
My Role
As CTO, I held overall technical responsibility: architecture, technology decisions, leading a team of up to six developers, and steering release and operations processes across the entire project.
The Decision
Build a platform that handles sensitive health data securely while staying maintainable for a small team over years. Modular approach: PHP/Symfony with API Platform as the core, Flutter for a cross-platform mobile app, Keycloak as a standalone IAM component instead of custom auth logic.
Trade-offs
- Flutter instead of native apps: faster development with a small team, at the cost of platform-specific polish.
- Keycloak instead of building auth ourselves: more operational overhead, but lower risk on something that isn't the actual value we deliver.
- On-premise instead of managed cloud: more operational responsibility of our own, but full control over health data.
Implementation
Containerized, automated infrastructure; invested early in a complete logging/monitoring pipeline — for a system I co-operated myself for three years, not a nice-to-have.
Result
Three years of stable production operation, team grown to six people.
Migrating an ERP System, Online Shop, and Website for a Retailer
Period: 2025 · Role: IT Consultant and Technical Lead · Industry: Retail
Context
A mid-sized retailer and e-commerce provider needed to replace three interconnected systems at once: ERP, online shop, and website. My most recent engagement, and the one with the largest share of custom tooling built for the migration itself.
My Role
Technical lead for the entire migration — target architecture, interface design, go-live planning, four-person team.
The Decision
Three source systems on three different database engines (PostgreSQL, MariaDB, Microsoft SQL Server) had to be migrated consistently to the new target systems (EULANDA ERP, OXID eShop, Grav CMS). Instead of stitching together existing migration tools, I built a custom migration tool in Go (Cobra, Gin, GORM).
Trade-offs
- Custom migration tool instead of an off-the-shelf one: higher upfront effort, but full control over sequencing, validation, and repeatability across three heterogeneous source systems.
- Go instead of PHP for the migration tool, even though the target shop itself runs on PHP (OXID): a deliberate separation between robust, type-safe migration logic and the existing target-system stack.
- Directus as a product management system instead of a leaner, pure PIM tool: more upfront ramp-up, but the option to also use it as a CMS later.
Implementation
A monitoring pipeline (Grafana, Promtail, Loki) for migration runs and system state during the cutover. Directus was introduced for product data management — currently as a product management system, with the potential to also serve as a CMS later.
Result
Successful migration of all three systems within 7 months.
IT Architecture Management for an Airline Group
Period: 2012 · Role: Solution Architect · Industry: Aviation
Context
Group-wide IT architecture governance for a major German airline group, as part of a three-person architecture team — the only engagement on this list without hands-on implementation, but with the widest organizational reach.
My Role
Solution Architect — assessing the existing IT landscape, defining guardrails and standards per domain, maintaining the IT landscape plan, leading the Architecture Working Group, and reporting to the Architecture Review Board.
The Decision
The question wasn't "which technology," but how dozens of parallel projects could avoid architectural conflict without one team deciding everything centrally. The answer: standards and guardrails per domain, with conformance checked through reviews and audits instead of central case-by-case decisions.
Trade-offs
- Guardrails instead of individual approvals: scales across many parallel projects, but costs precision in individual cases.
- An advisory role instead of direct authority: slower than a top-down mandate, but higher acceptance across business units because decisions were arrived at transparently rather than imposed.
Implementation
Alfabet planningIT as the central tool for IT landscape planning; architecture processes embedded into existing project phases rather than run as a separate gate process.
Result
Established, documented standards across all levels of the IT architecture pyramid, and working review/audit processes for ongoing projects.
More Projects
- ZairoSuite (My own company) – Founder, Solution Architect and DevOps Engineer. A modular software product portfolio for the digital presence of SMEs — not a client engagement, my own company. Actively developed, several modules already in production. More on the company website.
- Keycloak/Entra ID Migration for Moodle (2023–2024) – IT consultant for Identity & Access Management. Central IAM solution for Moodle and other education systems (Keycloak, Entra ID, OpenID Connect, SAML). Result: unified authentication and authorization concept on scalable cloud infrastructure.
- News Portal Administration (2019–2022) – DevOps Engineer. Multi-site infrastructure for a news portal, 3.5 years, team of 8. Result: stable operations throughout, full observability pipeline built.
- Online Ticketing System (2019–2020) – Software Engineer. Ticketing system for a trade-fair organization (Symfony, React, Keycloak). Result: production system including CI/CD and container deployment.
- Coexistence IT System for Less-Than-Truckload Freight (2012) – Partial project lead. Data-migration coexistence system for a global logistics provider, team of 25. Result: successful integration and data reconciliation between source and target systems.
- Automotive Configurator Rollout via the Internet (2009–2010) – Project lead for multiple markets. International rollout of a digital car configurator. Result: successful launch in several new markets within one year.
- New Development of an Online Pricing Tool (2006–2007) – Project lead. Web application for structured financial products, full ownership of the overall software architecture. Result: launched into production.
Further references available on request.