●Change8

Migrating to MLflow v3.13.0

Version v3.13.0 introduces 5 breaking changes. This guide details how to update your code.

Released: 6/1/2026

5
Breaking Changes
3
Migration Steps
8
Affected Symbols

⚠️ Check Your Code

If you use any of these symbols, you need to read this guide:

mlflow.models.servemlflow autolog claudejudge.align()mlflow.get_traceRunner.run_streamed()mlflow.source.nameLiveSpan.add_link()prompt

Breaking Changes

●Issue #1

The permission system was overhauled into a unified Role-Based Access Control (RBAC) model. Legacy per-resource permission tables, REST endpoints, and client methods are removed. Code relying on old per-resource permission APIs must migrate to the new role-based APIs. The `default_permission` now acts as a floor instead of an override, and a workspace `USE` grant is sufficient to create experiments and registered models.

●Issue #2

MLServer is no longer available as a pyfunc serving backend. The deprecated `enable_mlserver` option is removed; `mlflow models serve` now exclusively uses the built-in scoring server.

●Issue #3

`mlflow autolog claude` no longer installs the old Python autolog hook. Claude Code tracing is now provided by an official plugin that must be installed separately.

●Issue #4

The default optimizer used by `judge.align()` is now MemAlign, which may cause existing alignment workflows to produce different judges unless an optimizer is explicitly passed.

●Issue #5

Pointing the tracking or model registry store at a local file-system path raises an error by default. Set `MLFLOW_ALLOW_FILE_STORE=true` environment variable to retain file-based store usage.

Migration Steps

  1. 1
    Migrate code that relied on the old per-resource permission APIs to use the new role-based APIs.
  2. 2
    If using file-system paths for tracking or model registry stores, set the environment variable `MLFLOW_ALLOW_FILE_STORE=true` to maintain this behavior.
  3. 3
    If using `mlflow autolog claude`, ensure the official Claude plugin is installed separately to receive tracing.

Release Summary

MLflow 3.13.0 introduces a major overhaul with a full Role-Based Access Control (RBAC) system and Admin UI, alongside new features for trace archival and enhanced AI Gateway/Assistant support. This release contains breaking changes related to the permission APIs and the removal of MLServer as a serving backend.

Need More Details?

View the full release notes and all changes for MLflow v3.13.0.

View Full Changelog