The four pillars
MLflow's mission, in one sentence
Keep the artefacts and metadata of every ML experiment together > for as long as you need them.
It is built around four pillars:
| Pillar | What it solves |
|---|---|
| Tracking | Records params, metrics, artifacts, code version, environment per run. |
| Projects | Packages code + environment so anyone can mlflow run . and get the same result. |
| Models | Standard packaging (a flavor) so the same model can be loaded by sklearn, PyTorch, or as a generic pyfunc. |
| Registry | A versioned catalog: None → Staging → Production → Archived, with aliases, lineage and audit. |
What MLflow is not:
- not a feature store (use Feast/Tecton),
- not an orchestrator (use Airflow/Prefect/Dagster),
- not a monitoring tool (use Evidently/Arize/WhyLabs),
- not opinionated about the model framework — that's the point.