Stefan Koshiw

Profile

I work as the CTO at Fraud0. Alongside that, I advise pre-seed teams on technical decisions and act as a sounding board for early product ideas, helping them avoid mistakes that are hard to fix later.

Over the years I’ve moved from building real-time ray tracers for CAD systems, to payment fraud in fintech, and now ad tech. My roles have always involved writing code, though in recent years I’ve spent more time on management - building teams, setting direction, and making sure the system around the code holds up.

Lately, I’ve been building and testing generative AI systems: agent-style workflows, voice-based interfaces, RAG architectures, and semantic knowledge graphs. I find the space both exciting and unsettling, in terms of what is possible and what it means for the future of work.

When I’m not working, I read a lot, cook often, and go bouldering.