8 Best MLflow Alternatives in 2026 (Open Source)
MLflow — Open-source AI engineering platform for agents, LLMs, and ML models. The largest open source AI engineering platform with comprehensive observability and evaluation features specifically designed for agents and LLM applications.
Short answer
- Closest match to MLflow: Langfuse.
- Most actively developed: Agenta (8,893 commits in the last 90 days).
- Fastest growing: Langfuse (+1,812 GitHub stars in the last 30 days).
These 8 open-source tools do the same job. They are ordered by how closely they match MLflow, with live GitHub data so you can see which projects are actively maintained.
| Tool | GitHub stars | Stars / 30d | Last commit |
|---|---|---|---|
| MLflow(original) | 28.2k | +480 | 2026-10-02 |
| Langfuse | 35.3k | +1,812 | 2026-10-02 |
| phoenix | 11.7k | +416 | 2026-10-02 |
| Opik | 22.3k | +607 | 2026-10-02 |
| langwatch | 4.9k | +275 | 2026-10-02 |
| Agenta | 4.8k | +130 | 2026-10-02 |
| OpenLIT | 2.8k | +77 | 2026-10-01 |
| TensorZero | 11.7k | +89 | 2026-06-04 |
| helicone | 6.2k | +133 | 2026-09-16 |
1. Langfuse
Open-source LLM engineering platform for observability, evaluation, prompt and dataset management
What sets it apart: Unlike LangSmith (LangChain-specific) or Helicone (proxy-based), Langfuse is fully open-source, framework-agnostic, and self-hostable, combining tracing, prompt management, evaluations, and datasets in a single platform built on ClickHouse for scalable production use.
Best for: Teams operating production LLM applications who need tracing, prompt management, and evaluation in one platform; Organizations requiring self-hosted LLM observability for data privacy compliance
2. phoenix
AI Observability & Evaluation
What sets it apart: Full-stack AI observability (tracing + eval + datasets + prompt management) in one open-source platform — vs LangSmith which is closed-source and LangChain-specific
Best for: Debugging and monitoring LLM applications in production; Systematic prompt engineering and experiment tracking
3. Opik
Debug, evaluate, and monitor your LLM applications, RAG systems, and agentic workflows with comprehensive tracing, automated evaluations, and production-ready dashboards.
What sets it apart: Full-lifecycle LLM platform combining tracing, evaluation, and optimization — uniquely includes Agent Optimizer and Guardrails alongside observability, unlike trace-only tools like LangSmith
Best for: Teams needing end-to-end LLM observability from development to production; Automated LLM evaluation and quality assurance in CI/CD pipelines
4. langwatch
The platform for LLM evaluations and AI agent testing
What sets it apart: Unified platform combining agent simulation, evaluation, observability, and prompt optimization with OpenTelemetry-native design — vs separate tools for tracing (Langfuse), eval (DeepEval), and prompt management
Best for: Teams wanting eval + observability + prompt management in one tool; Agent simulation testing before production deployment; Organizations needing OpenTelemetry-native LLM observability
5. Agenta
The open-source LLMOps platform: prompt playground, prompt management, LLM evaluation, and LLM observability all in one place.
What sets it apart: Unified open-source LLMOps platform combining prompt playground, version control, 20+ evaluators, and OTel-native observability in one tool — vs separate tools for each
Best for: Teams needing integrated prompt management + evaluation + observability; Product teams collaborating with SMEs on prompt engineering; Organizations wanting open-source LLMOps alternative
6. OpenLIT
Open-source platform for AI agent tracing, evaluations, guardrails, prompts, and GPU monitoring
What sets it apart: Most comprehensive open-source AI engineering platform — combines observability, 11 evaluation types, rule engine, prompt hub, secret vault, playground, and fleet management in one tool
Best for: Teams wanting all-in-one LLM platform (observability + eval + prompts + secrets); Organizations needing self-hosted AI engineering platform; Multi-language teams (Python/TS/Go SDK support)
7. TensorZero
TensorZero is an open-source LLMOps platform that unifies an LLM gateway, observability, evaluation, optimization, and experimentation.
What sets it apart: Only LLM gateway that combines inference, observability, evaluation, and optimization in one Rust-based system with data flywheel — vs LiteLLM (routing only) or Langfuse (observability only)
Best for: Teams wanting a unified LLM gateway with built-in optimization feedback loop; Production systems needing <1ms latency overhead at scale; Organizations wanting to continuously improve LLM performance from production data
8. helicone
🧊 Open source LLM observability platform. One line of code to monitor, evaluate, and experiment. YC W23 🍓
What sets it apart: vs LangSmith/Braintrust: Combined AI Gateway + Observability platform with one-line integration, generous free tier, unified access to 100+ models, and built-in prompt versioning - Y Combinator backed
Best for: Teams needing unified observability across multiple LLM providers; Production AI apps requiring cost tracking and prompt management; Developers wanting a single API gateway for 100+ models
FAQ
- What are the best alternatives to MLflow?
- The closest open-source alternatives to MLflow are Langfuse, phoenix and Opik, followed by langwatch, Agenta and OpenLIT. They are ranked by how closely they match what MLflow does.
- Which MLflow alternative is the most popular?
- Langfuse has the most GitHub stars among MLflow alternatives, with 35,301 stars.
- Which MLflow alternative is the most actively maintained?
- By recent activity, Agenta (8,893 commits in the last 90 days) is the most actively developed alternative.