Fendlemark v0.9.5

Documentation

Migrating from 0.8 to 0.9

Fendlemark 0.9.0 renamed one configuration key. This guide exists because the Keepers hold that every breaking change, however small, deserves a document proportionate to the trust it asks of you.

Summary of changes

0.80.9Type
adapters.mlflow.trackingUriadapters.mlflow.tracking_uriRenamed

That is the complete list. The old spelling is accepted with a deprecation warning (DOC-104) through the 0.9 series and will be removed in 0.10.

Why

Every other key in fendlemark.yaml is snake_case. trackingUri was camelCase because the first Keeper wrote it at 02:14 on 11 March 2023 while copying the name from MLflow's Python client, and nobody noticed for two and a half years. When it was noticed, it was raised as a Pre-Intent Notice, discussed across three Reflection Periods, and resolved in FDR-041, which also records the Keepers' view that "a single inconsistency in a correct system is not a small thing; it is the only thing".

Before you begin

  1. Confirm you are on 0.8.2 or later. Earlier 0.8 releases should first upgrade to 0.8.2, which changed nothing but was released anyway.
  2. Back up fendlemark.yaml. fendlemark doctor --fix does this for you, but the Keepers prefer that you do it yourself, once, deliberately.
  3. Read the Philosophy. Not for the migration. For you.

Migration

Automatic

$ fendlemark doctor --fix
config    warn     DOC-104 adapters.mlflow.trackingUri is the pre-0.9 spelling; use tracking_uri (fixable)
          fixed    renamed adapters.mlflow.trackingUri → adapters.mlflow.tracking_uri
          backup   fendlemark.yaml.bak-20261024T091203Z

Manual

adapters:
  mlflow:
    enabled: true
-   trackingUri: "http://mlflow.internal:5000"
+   tracking_uri: "http://mlflow.internal:5000"

Environment variable form

# before
FENDLEMARK_ADAPTERS__MLFLOW__TRACKINGURI=http://mlflow.internal:5000
# after
FENDLEMARK_ADAPTERS__MLFLOW__TRACKING_URI=http://mlflow.internal:5000

Verification

$ fendlemark doctor
config    ok       ./fendlemark.yaml (6 keys set, 41 defaulted)
$ fendlemark adapters check mlflow
ADAPTER    STATUS    LATENCY   DETAIL
mlflow     healthy   41ms      12 experiments, 1,406 runs visible

If the detail line matches what you saw before the migration, the migration is complete. It will.

Rollback

Restore the backup and run 0.8.2. Because 0.9 accepts both spellings, you may also simply run 0.9 with the old key and ignore the warning, though the Keepers would know.

Frequently asked questions

Is this really the only change in 0.9.0?

It is the only breaking change. 0.9.0 also included the serene log level, the explain subcommand, and 212-parameter respiratory signatures (up from 208). None of those require action.

Why a whole page for one key?

Because you will search for it at 02:14, and you deserve to find a page that treats your time as if it mattered.

Will there be a 0.10 migration guide?

If anything changes, yes. The Keepers have no roadmap, so nothing is currently planned to change. See the Philosophy on roadmaps.

What about @fendlemark/ui?

No changes. The component library's props have been stable since 0.7.