Seed · AI & Machine Learning · Berlin, Germany · Founded 2022 · 7–13 employees
Langfuse is an open-source LLM engineering platform that provides observability, analytics, and debugging tools for large language model applications. Founded in 2022 and backed by Y Combinator W23, the company has achieved remarkable adoption with over 23,000 GitHub stars, 23M+ monthly SDK installs, and usage by 19 Fortune 50 companies. The platform helps developers trace, evaluate, and improve LLM applications through features like prompt management, cost tracking, and automated evaluations. In January 2026, Langfuse was acquired by ClickHouse to accelerate development of unified observability infrastructure.