Langfuse
Open-source LLM engineering platform with observability and evaluation
About Langfuse
Langfuse is an open-source platform for LLM application development that provides tracing, prompt management, evaluation pipelines, and cost tracking. It integrates with major LLM frameworks through OpenTelemetry and supports both self-hosted and managed cloud deployments. With 21,000+ GitHub stars it is one of the most widely adopted open-source tools in the LLM observability space.