Critical thinking
for code, AI & process.
I take on technical leadership where it counts – from architecture decisions and code reviews to clean AI integration in production systems.
Worked with
With his strong problem-solving skills, he resolved the most complex situations for himself and other team members.
Three ways to work with me.
Clearly scoped, transparently priced. Pick the one that fits your phase – or combine them into a custom engagement.
Architecture & AI Review
A second opinion on your backend architecture, API strategy, or AI integration. Delivers a prioritized briefing in five working days.
- ✓ 5-day deep dive, incl. kickoff & readout
- ✓ Written report with risks & quick wins
- ✓ 30-day follow-up call
Fractional Tech Lead
2–3 days per week of technical leadership for your backend or dataspace team. Architecture, code reviews, mentoring – and hands-on where it matters.
- ✓ Technical leadership & architecture ownership
- ✓ Hands-on Kotlin / Java / Quarkus / TypeScript
- ✓ Code & PR reviews, hiring support
- ✓ 3-month minimum · monthly cancellation
AI Enablement for Teams
A structured program that makes your team productive with AI coding assistants and automations – without losing quality.
- ✓ Workshop (2 days) · guidelines · playbooks
- ✓ Review process for AI-generated code
- ✓ Pilot project with measurable goals
None of these fit?
Longer-term engagements, research projects or a special scope – drop me a line with what you have in mind.
All prices excl. VAT · Based in Cologne, remote-friendly. Confidential. GDPR-compliant.
Client Testimonials
What my clients say about working together
Jan supported us in building a new medical startup on the technical side. I value his reliability, straightforward communication, and great teamwork.
Stephan M. Czaja
CEO, CXMXO
Jan supported our team as a backend developer across multiple software projects, and I can only praise his skills and qualities. Jan is a very structured and experienced developer. With his strong problem-solving skills, he resolved the most complex situations for himself and other team members. Beyond his technical abilities, Jan is also a great teammate. His communication skills and willingness to share knowledge quickly made him a valued member of our team.
Dr. Sebastian Opriel
CTO, sovity GmbH
Our website "Xenophon" is so easy to use - you can find everything at a glance. Important things catch your eye. Finally, a site that isn't overloaded with a thousand things. And the best part: we have the site maintained, so everything is always up to date. Nothing is worse than a site that isn't current or responds slowly.
Board of Directors
Xenophon e. V.
Core Competencies
The strengths I bring to every project
Critical Thinking
Systematic analysis of complex technical challenges to make well-founded, sustainable decisions.
Problem Solving
Translating ambiguous requirements into clean, maintainable architectures - efficiently and purposefully.
AI Engineering
Designing and integrating intelligent systems and AI-powered workflows into production-ready applications.
Backend & API Architecture
Building scalable, well-documented APIs and robust backend systems that power modern applications.
Technologies & Tools
The tools I work with
Languages
Frontend & Backend
DevOps & Infrastructure
AI & LLM Engineering
Tools & Platforms
Dataspace & Domain
Professional Experience
My career journey
sovity GmbH - Lead Application Development
CurrentJuly 2025 – present
Leading application development in the Catena-X and dataspace ecosystem. Responsible for architecture decisions, code quality, and team growth.
sovity GmbH - Full-Stack Developer
January 2025 – June 2025
Full-stack development in the Catena-X ecosystem within an agile team. Designed and implemented new features based on Eclipse Dataspace Components (EDC) - in parallel with freelance work.
Freelance Software Engineer
CurrentApril 2023 – present
Designing and building custom web applications and backend systems for SMEs, educational institutions, and non-profit organizations. Consulting on software architecture and technology strategy.
TU Dortmund - Computer Science, B. Sc.
October 2016 – April 2023
Bachelor's degree in Computer Science with a minor in Theoretical Medicine. Solid foundation in algorithms, software engineering, and systems programming.
G DATA CyberDefense AG - Test Automation Engineer
August 2020 – March 2023
Built and maintained end-to-end test automation infrastructure. Designed testing strategies to secure CI/CD pipelines for enterprise security products.
communicode AG - DevOps Engineer
August 2019 – July 2020
Developed a deployment prototype to streamline development and delivery workflows for client websites. Automated build and release processes.
bee42 solutions GmbH - DevOps Engineer
January 2019 – July 2019
Delivered DevOps training and technical consulting. Built prototypes and organized a professional conference.
Fraunhofer ISST - Mobile Developer
March 2017 – December 2018
Developed a mobile application to support epilepsy patients in daily life, integrated with a sensor-based monitoring system.