Marc Klingen

Co-founder & CEO | Langfuse

Marc Klingen is the Co-Founder and CEO of Langfuse, the leading open-source LLM engineering platform for observability, evaluations, and prompt management. Backed by Y Combinator (W23), Lightspeed, and General Catalyst, Langfuse has grown to 22,000+ GitHub stars, 23M+ monthly SDK installs, and is trusted by 19 of the Fortune 50 — including customers like Merck, Canva, Twilio and Khan Academy. In early 2025, Langfuse was acquired by ClickHouse to deepen its data infrastructure. He is based in Berlin.