← AI Terminology

Model Registry

A model registry is a central catalogue of trained model versions with metadata, lineage, stage labels (staging/prod), and approval workflows.

It is the source of truth for what runs in production.
Why It Matters in AI
Without a registry, teams lose track of which checkpoint is live. Registries enable audit, rollback, and promotion gates — mandatory governance for regulated ML and helpful for all AI products.
Key Points
Aspect Description
Tools MLflow Model Registry, W&B Artifacts, cloud registries
Access RBAC on who can promote to prod
Stages None → Staging → Production → Archived
Stores Weights refs, metrics, signatures, lineage
Related MLOps, experiment tracking
LLM twist Also track prompts, LoRA adapters, base model IDs
Simple Analogy
A library card catalogue for models — every edition labeled, who approved it, and which branch is checked out to the reading room (prod).
Common Usage Examples
  • mlflow.register_model
  • Promote v12 to Production stage
  • Deploy pulls only Production alias
  • Lineage: dataset v3 → model v12
Summary
In short: A model registry catalogues versioned models and their stages — the control plane for safe promotion and rollback.