MLflow
Open-source platform for LLM tracing, evaluation and prompt management plus classic ML experiment tracking and model registry.
Quick answer
MLflow is an open-source platform for LLM tracing, evaluation and prompt management plus classic ML experiment tracking and model registry, listed under LLM gateway & observability. A typical small-business use: trace what a support chatbot or agent did on each request and where it went wrong. The project publishes no official RAM figure, so we do not estimate a monthly server cost. License: Apache-2.0, which allows internal business use.
Last updated · facts verified against official docs on · sources
Activity data comes from GitHub and was last refreshed Nov 1, 2026.
What is MLflow?
MLflow is a long-running open-source MLOps platform that now covers LLM and agent apps too. It records traces of LLM calls and agent steps (OpenTelemetry-compatible), runs evaluations with LLM judges, versions prompts in a prompt registry, and includes an AI gateway for routing requests to model providers. The classic features remain: experiment tracking and a model registry. A single tracking server with a web UI serves the whole team; it runs on SQLite by default and scales to PostgreSQL with artifacts in S3, GCS or Azure Blob Storage.
Where it fits in a 10–200 person business
- Trace what a support chatbot or agent did on each request and where it went wrong
- Compare prompt or model changes with repeatable evaluations before rolling them out
- Track fine-tuning or classic ML experiments and keep a registry of approved model versions
These use cases are our editorial suggestions, not claims made by the project.
Can a business use MLflow? (license)
| License | Apache-2.0 |
|---|---|
| Type | Permissive: MIT / Apache-2.0: use, modify and sell with few obligations. |
| Internal business use | Allowed under the license text |
| What to watch | Free for internal and commercial use, modification and redistribution. Keep the license and notices. |
This is a plain-English summary of the license text, not legal advice. Third-party models you run with it have their own licenses.
Data & compliance: does MLflow phone home?
| Telemetry (usage data sent to the vendor) | On by default Anonymized usage data is collected by default since 3.2.0; the docs list each event and state it contains no personal data. How to turn it off: Set MLFLOW_DISABLE_TELEMETRY=true or DO_NOT_TRACK=true. |
|---|---|
| Other calls home by default (updates, marketplaces, default cloud services) | Yes, by default The default usage-data collection sends anonymized events to MLflow unless disabled. |
| Single sign-on (OIDC / SAML / LDAP) | Free By protocol: OIDC free. Not built in. The docs point to the community-maintained mlflow-oidc-auth plugin for OIDC, or to a reverse proxy such as oauth2-proxy in front of MLflow. |
| Audit log | Not documented |
| Role-based access control (RBAC) | Yes, free With basic auth enabled, admins assign users roles and per-resource permissions (READ, EDIT, MANAGE); roles become workspace-scoped when workspaces are enabled. Source: mlflow.org/docs/latest/self-hosting/security/role-based-access-control |
| Data residency / GDPR notes from the project | Not documented |
Checked against the project's own docs and repository on . "Not documented" means we could not find the answer in official sources; it does not mean the feature is missing or that no data is sent. Third-party services you connect (model APIs, vector databases, search engines) have their own data policies. Compare all apps.
What hardware does MLflow need?
The project does not publish a minimum CPU/RAM figure, so we leave the official value blank rather than guess.
GPU: No.
No CPU, RAM or disk requirements are published. The quickest setup is a single process with SQLite and local artifact storage; the Docker Compose bundle adds PostgreSQL and RustFS (S3-compatible storage).
How much does it cost to host MLflow per month?
The project publishes no RAM figure we could verify, so we do not estimate a cost.
How to deploy MLflow
Method: Docker Compose (MLflow + PostgreSQL + RustFS)
git clone https://github.com/mlflow/mlflow.git
cd mlflow/docker-compose
cp .env.dev.example .env
# change the default passwords in .env first
docker compose up -d
# open http://localhost:5000
# quickest alternative: pip install mlflow && mlflow server --port 5000 From the official instructions: mlflow.org/docs/latest/self-hosting/. Always check the source for the current version before you run it.
Known gotchas when self-hosting MLflow
- Authentication is off unless you start the server with --app-name basic-auth. That mode needs MLFLOW_FLASK_SERVER_SECRET_KEY and an admin password in MLFLOW_AUTH_ADMIN_PASSWORD set before the first start, or the server refuses to start. source
- Anonymized usage data is collected by default since version 3.2.0. Set MLFLOW_DISABLE_TELEMETRY=true or DO_NOT_TRACK=true to opt out. source
- The Compose example .env ships default credentials (POSTGRES_PASSWORD=mlflow, AWS_SECRET_ACCESS_KEY=s3admin) and binds MLflow to 0.0.0.0. Change them before exposing the server. source
- The built-in protection against DNS rebinding, CORS attacks and clickjacking (3.5.0+) only works with the default uvicorn server, not with --gunicorn-opts or --waitress-opts. When serving on 0.0.0.0, set --allowed-hosts to your real hostnames. source
Alternatives in LLM gateway & observability
- LiteLLM AI gateway that puts 100+ LLM providers behind one OpenAI-compatible API with keys and budgets.
- New API Self-hosted AI API gateway (One API fork) that puts many model providers behind one key, with quotas, usage logs and cost tracking.
- One API Original self-hosted LLM API gateway that puts many model providers behind one OpenAI-style key, with quotas and token management.
- Langfuse LLM observability with tracing, prompt management, evaluations and cost tracking.
- Opik Open-source LLM observability and evaluation platform for tracing, evals, prompt management and monitoring.
- Phoenix Free self-hosted LLM tracing, evaluation, datasets and prompt management from Arize.
MLflow FAQ
How much RAM does MLflow need?
MLflow does not publish an official RAM figure, so we do not state one. No CPU, RAM or disk requirements are published. The quickest setup is a single process with SQLite and local artifact storage; the Docker Compose bundle adds PostgreSQL and RustFS (S3-compatible storage).
Does MLflow need a GPU?
No.
How much does it cost to self-host MLflow?
The software is free to download. The project publishes no official RAM figure, so we do not estimate a monthly server cost.
Is MLflow free for commercial use?
MLflow is licensed under Apache-2.0 (Permissive). Internal business use is allowed under the license text. Free for internal and commercial use, modification and redistribution. Keep the license and notices. This is a summary, not legal advice.
What are common problems when self-hosting MLflow?
Authentication is off unless you start the server with --app-name basic-auth. That mode needs MLFLOW_FLASK_SERVER_SECRET_KEY and an admin password in MLFLOW_AUTH_ADMIN_PASSWORD set before the first start, or the server refuses to start. Anonymized usage data is collected by default since version 3.2.0. Set MLFLOW_DISABLE_TELEMETRY=true or DO_NOT_TRACK=true to opt out. The Compose example .env ships default credentials (POSTGRES_PASSWORD=mlflow, AWS_SECRET_ACCESS_KEY=s3admin) and binds MLflow to 0.0.0.0. Change them before exposing the server. The built-in protection against DNS rebinding, CORS attacks and clickjacking (3.5.0+) only works with the default uvicorn server, not with --gunicorn-opts or --waitress-opts. When serving on 0.0.0.0, set --allowed-hosts to your real hostnames.
Is MLflow still maintained?
Yes, it is actively developed. Last commit: Nov 1, 2026. Latest release: v3.17.2 (Oct 21, 2026). Checked Nov 1, 2026.
How do I install MLflow?
The official method is Docker Compose (MLflow + PostgreSQL + RustFS). The exact commands are in the "How to deploy" section above and in the official instructions: https://mlflow.org/docs/latest/self-hosting/
What are self-hosted alternatives to MLflow?
Other apps in LLM gateway & observability: LiteLLM, New API, One API, Langfuse, Opik, Phoenix.
Sources
- GitHub repository: github.com/mlflow/mlflow
- Official documentation, Hardware requirements, Deploy instructions: mlflow.org/docs/latest/self-hosting/
- License text: github.com/mlflow/mlflow/blob/master/LICENSE.txt
- Gotcha 1: mlflow.org/docs/latest/self-hosting/security/basic-http-auth/
- Gotcha 2: mlflow.org/docs/latest/community/usage-tracking/
- Gotcha 3: github.com/mlflow/mlflow/tree/master/docker-compose
- Gotcha 4: mlflow.org/docs/latest/self-hosting/security/network/
- Hetzner Cloud pricing (cost estimate): www.hetzner.com/cloud/regular-performance
- GitHub stars, commits and releases: GitHub REST API, fetched
Facts on this page were checked against the project's own repository and docs on 2026-11-01. Spotted something out of date? Tell us.