Java Developer
From Day One

My first computer – a TI-99/4A. I typed in BASIC programs from magazines, understood them, modified them. Ever since, I’ve wanted to know what really happens inside software.

Diplom-Informatiker with distinction (grade 1.2). Focus: algorithms and data structures and database systems – the foundation I still build on today.

In 1996, I read about a new language called Java in c’t magazine. After years of C++, garbage collection and “write once, run anywhere” fascinated me instantly – I convinced my professors to let me submit my programming assignments in Java from then on. My first application: an applet simulating flip-flops.

As an intern and thesis student, I worked on data-driven decision-making processes – long before “Big Data” became a buzzword. My first hands-on encounter with scalability, handling millions of concurrent requests.

As co-founder and CTO of Cleverlearn, I developed interactive language-learning software, with the entire backend in Java. My first company – and the realization that a product only counts when people actually use it.

At jfax.de, I developed messaging and enterprise features in Java for one of the largest German internet portals of its time – right in the middle of the dotcom era. Heavy loads, tight deadlines, no second chances.

As co-founder and CTO of W+R Software GmbH, I built the GMX SMS Manager – one of the first paid online messaging services in Germany. Millions of users, millions of messages per day – real-world scaling.

After the acquisition by 1&1, I continued leading the Windows client team and reimplemented the SMS backbone in Java. For the first time, it wasn’t just about code, but about people, processes, and how a team grows stronger together.

As founder and CTO of eleisure AG, I built online platforms and browser games – including GameAbo and Feenix – The Age of Pirates, all backends entirely in Java. My key takeaway from this era: good architecture only pays off when the team understands and can maintain it.

As co-founder and CTO, I built and scaled AndroidPIT for ten years – from a Berlin startup to an international tech publisher with millions of readers per month, with the backend entirely in Java. Growing alongside it: the developer team I built up.

At IONOS, I worked on high-performance Java backends in the cloud and pushed to lift services to current Java versions and adopt new language features. The focus: making systems faster and more robust – and enabling the team behind them to maintain that quality on their own.

At ICE, I focus on the scalability and performance of Java services under real-world load. Huge data volumes, demanding requirements, no excuses – exactly the kind of problems I most enjoy tackling. I push modernization forward here too: with version upgrades, new services built on current Java, and live sessions on new Java features.

With HappyCoders, I bundle my Java experience into articles, videos, my newsletter, and Java trainings. My goal: give Java teams the tools to use modern features effectively – so they can develop faster, write clearer code, and build more stable applications.