Langfuse vs OpenLLMetry
Both are alternatives to LangSmith. Here's how they stack up — verified facts, no spin.
Also searched as OpenLLMetry vs Langfuse — same comparison, one verdict.
Langfuse
TOP PICKThe self-hosted default for LLM tracing — MIT core, framework-agnostic.
Langfuse is the most widely adopted open LLM observability platform: tracing, evaluation, prompt management and cost tracking, deployable with Docker on your own infrastructure so traces containing customer data never leave your network. It is deliberately framework-agnostic — LangChain, LlamaIndex, the provider SDKs directly, or OpenTelemetry — which makes it the natural exit from a LangChain-shaped tool. At 32k stars with commits landing daily it is the healthiest project in this category. Licensing needs precision: the core is MIT Expat, while the ee/ directories carry a separate enterprise licence.
OpenLLMetry
Apache-2.0 OpenTelemetry instrumentation — send traces anywhere you already send them.
OpenLLMetry takes the opposite approach to a platform: it is a set of Apache-2.0 OpenTelemetry extensions that emit LLM traces in a standard format, so they flow into whatever you already run — Grafana, Datadog, Honeycomb, Jaeger or Traceloop's own hosted backend. If you already have observability infrastructure, this adds LLM visibility to it rather than asking you to adopt a second, parallel system. It is also the strongest hedge against lock-in: standard telemetry moves between backends by configuration.
Side by side
| Langfuse | OpenLLMetry | |
|---|---|---|
| Sovereignty Score | 90 | 92 |
| Open source | Yes | Yes |
| Self-hostable | Yes | Yes |
| Local-first | Yes | Yes |
| License | MIT Expat (core); ee/ directories under a separate enterprise licence | Apache-2.0 |
| Pricing | Free to self-host — Docker Compose or Kubernetes, costs are your own infrastructure. A managed cloud with a free tier and paid plans exists if you would rather not run it. | Free — Apache-2.0 instrumentation libraries. You pay only whatever backend you already send telemetry to; a hosted Traceloop backend is available separately. |
Langfuse is Macrostack's recommended LangSmith alternative, so it's our pick here.
Langfuse
Strengths
- +Self-hosted: prompts and completions stay inside your network
- +Framework-agnostic — not tied to any one orchestration library
- +Tracing, evals, prompt management and cost tracking in one tool
- +32k stars and daily commits — the most active project in this category
Trade-offs
- −Self-hosting means running Postgres, ClickHouse and the collector yourself
- −The MIT core stops at the ee/ directories; SSO and some enterprise features sit behind a separate licence
- −Evaluation tooling is less polished than LangSmith's if you live inside LangChain
- −Trace storage grows fast — retention policy is your problem to plan
OpenLLMetry
Strengths
- +Apache-2.0 throughout — no enterprise-directory carve-out
- +Standard OpenTelemetry: traces go to a backend you already operate
- +The best protection against lock-in — switching backends is configuration
- +Reuses your existing observability stack instead of adding a parallel one
Trade-offs
- −Instrumentation, not a platform — no evaluation or prompt-management UI
- −You need a trace backend already, or you are choosing one anyway
- −Generic backends render LLM traces less legibly than a purpose-built UI
- −Smaller project (about 7k stars) than Langfuse
Related alternative guides
Facts verified 2026-07-30. Licenses and pricing change — spotted something out of date? That's a correction we want.