Langfuse

About Langfuse

Langfuse is an open-source LLM engineering platform that helps teams build useful AI applications through tracing, evaluation, and prompt management. Positioned as the 'Datadog' of LLM observability, the platform serves 19 of the Fortune 50 companies and over 2,000 customers with more than 26 million monthly SDK downloads. The company was acquired by ClickHouse in January 2026 to leverage data infrastructure capabilities while maintaining its commitment to open source and self-hosting. Langfuse provides framework integrations with 40+ LLM frameworks and model providers, enabling developers to instrument their AI applications seamlessly.