Langfuse

observability

Properties

vendor: Langfuse (ClickHouse)
url: https://langfuse.com/
whatItIs: Open-source AI engineering platform for collaborative debugging, tracing, and evaluation of LLM applications with managed and self-hosted options.
hosting: both
pricingModel: Free 50k/mo, Core $29/mo, Pro $199/mo, Enterprise $2,499+
modelProviders: agnostic
stateModel: trace-based sessions
toolModel: SDK + dashboard + 100+ integrations (OpenTelemetry first)
includesBrowser: false
includesMemory: false
longRunning: unlimited
hitlSupport: true
observability: tracing + LLM-as-judge + code + user-feedback evals
maturity: ga
launched: 2023
notes: Apache 2.0 licensed. OTEL-first. 20k+ stars by 2026. YC W23. Acquired by ClickHouse, Inc. in January 2026 alongside ClickHouse's $400M Series D; Langfuse stays open source under its existing license and Langfuse Cloud continues to run.

observability

vendor: Langfuse (ClickHouse)
url: https://langfuse.com/
whatItIs: Open-source AI engineering platform for collaborative debugging, tracing, and evaluation of LLM applications with managed and self-hosted options.
hosting: both
pricingModel: Free 50k/mo, Core $29/mo, Pro $199/mo, Enterprise $2,499+
modelProviders: agnostic
stateModel: trace-based sessions
toolModel: SDK + dashboard + 100+ integrations (OpenTelemetry first)
includesBrowser: false
includesMemory: false
longRunning: unlimited
hitlSupport: true
observability: tracing + LLM-as-judge + code + user-feedback evals
maturity: ga
launched: 2023
notes: Apache 2.0 licensed. OTEL-first. 20k+ stars by 2026. YC W23. Acquired by ClickHouse, Inc. in January 2026 alongside ClickHouse's $400M Series D; Langfuse stays open source under its existing license and Langfuse Cloud continues to run.