Langsmith Alternative? Langfuse vs. Langsmith

Is Langfuse a Langsmith Alternative?

The answer is yes, Langfuse is an open-source alternative to Langsmith.

How do Langsmith and Langfuse compare?

LangSmith and Langfuse are broadly similar products. They provide LLM observability, analytics, evals, testing and annotation.

What are the main differences between Langfuse and Langsmith

Langfuse is open source while LangSmith is a closed source project.
LangSmith is developed by the LangChain team and integrates very well with the LangChain framework. While Langfuse also maintains Langchain integrations, you may be better of choosing Langsmith if you plan to exclusively develop using the Langchain and Langgraph frameworks.
Langfuse maintains a large number of integrations into many frameworks and libraries. Langsmith focuses on its Langchain integration.
Langfuse can be self hosted at no cost while LangSmith needs to be purchased to be self hosted.

Is Langfuse related to Langsmith and Langchain?

No, Langfuse is independent to Langsmith and Langchain. Langsmith is a commercial offering by the same company that develops the open source Langchain LLM application framework.

While Langfuse integrates with the open source Langchain framework, the two organizations are separate and bear not relation. Langfuse and Langsmith operate in the same space and both try to help developers improve and iterate on their LLM applications.

Is Langsmith open source?

Langsmith is a closed source product. It is developed by the Langchain team which is developing the Langchain application framework in open source.

Can you self-host Langsmith?

Langsmith can be self-hosted but it requires a paid Enterprise License (opens in a new tab) to do so. It is a closed source project.

Langfuse can be freely self-hosted and is open source. Users can self-host Langfuse for in a FOSS (Free and Open Source) version while a paid Enterprise Edition with some additional features is also available.