// Profile

Technical depth meets
clear communication.

Freelance developer, consultant and trainer for modern web frontends. With a soft spot for making complicated things understandable and actionable.

I am a freelance developer, trainer and consultant for modern web frontends, working with clients since 2013. My focus is on Angular, TypeScript and HTTP APIs, covering everything from frontend architecture and accessibility through to operations and observability. Increasingly, AI in the frontend takes centre stage.

Having studied physics (MSc, University of Münster), I care deeply about getting the problem analysis right: I help teams make sound decisions and build solutions that stay maintainable. The frontend focus is backed by solid backend experience, including certification as an Oracle Certified Master, Java Developer.

I speak regularly at conferences such as JAX and the International JavaScript Conference, and write for outlets like entwickler.de and heise Academy about current trends and the reasoning behind them, for developers and architects alike. In my spare time I contribute to open source and co-organise the Java User Group Münster as well as the “Frontend Freunde” meetup.

MSc Physics Oracle Certified Master, Java Developer Conference speaker & author Open source contributor
Karsten Sitterberg talking with the audience during a conference session
In conversationMaking the complex understandableIn a workshop, inside a project team or on a conference stage: technology only becomes useful once it gets through.

// Community

Giving knowledge back

Knowledge grows through exchange, which is why I stay active in the developer community.

JUG Münster

Co-organiser of the Java User Group Münster, with regular talks and discussion around Java and the JVM.

Frontend Freunde

Co-founder of the “Frontend Freunde” meetup series for modern web development in Münster.

Open source

Contributions to open source projects. Good tools should benefit everyone.

// Contact

Let’s talk.

A project, a training request, an AI initiative in the frontend or an independent second opinion? Drop me a line and I’ll get back to you shortly.