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+# ADR-011: Rename the equipment domain to machines; retype the models catalog with modeltypes
+
+- **Status:** ACCEPTED
+- **Date:** 2026-07-11
+- **Deciders:** cproudlock
+- **Relates to:** ADR-005 (equipment vs measuringtools scope), ADR-008 (plugin migration ownership)
+
+## Context
+
+ADR-005 split the old "equipment" concept: gage-lab instruments moved to the
+measuringtools plugin, leaving the equipment plugin holding exactly one thing -
+shop-floor machines (lathes, mills, CMMs, grinders, furnaces). The UI, the
+routes (`/machines`), the frontend view folder (`views/machines/`), and even
+the data vocabulary (asset numbers headed "MACHINE #") already said machines.
+Only the code identity still said equipment: the plugin name, the API prefix,
+the `equipment`/`equipmenttypes` tables, and the `assettype='equipment'` data
+value. Every future contributor would pay a small permanent translation tax.
+
+A display-label-only swap was shipped first (2026-07-11) and immediately showed
+the dissonance: UI Machines over code equipment forever.
+
+Separately, the legacy `machinetypes` table survived the Machine-model
+retirement for one real reason: it types the vendor **models catalog**
+(`models.machinetypeid`, 95 of 127 models) with fine-grained, cross-category
+types (Lathe, Switch, Laser Printer). Its name was a misnomer - it never typed
+machines specifically - and it squatted on the name the machines plugin's
+subtype table wants.
+
+The economics favor doing this now and never again: the plugin contract is
+pre-1.0 (breaking changes are cheap per ADR-002), no sister site has adopted
+yet, there is no production instance, and the test suite plus CI give the
+strongest safety net the project has had.
+
+## Decision
+
+Rename the domain in one coordinated pass:
+
+| Current | New | Rationale |
+|---|---|---|
+| `plugins/equipment/`, `/api/equipment`, `equipment.*` perms | `plugins/machines/`, `/api/machines`, `machines.*` | plugin identity matches the domain |
+| `equipment` table, `equipmentid` | `machines`, `machineid` | main entity |
+| `equipmenttypes`, `equipmenttypeid`, `equipmenttype` | `machinetypes`, `machinetypeid`, `machinetype` | subtypes take the freed name |
+| legacy `machinetypes`, `models.machinetypeid` | `modeltypes`, `models.modeltypeid` | role-accurate: it types the models catalog, losslessly (no collapse to the 4 asset types) |
+| `assettypes.assettype = 'equipment'` (data) | `'machine'` | the string compare sites flip with it |
+
+Migration placement follows ADR-008: the modeltypes rename and the data flips
+land in the core chain (core tables, core data); the plugin table renames land
+in the machines plugin's own chain, idempotently guarded so fresh installs
+(whose core chain still creates the old names at `7c04`) rename on first
+`flask plugin upgrade-all`. The `alembic_version_equipment` version table is
+renamed to `alembic_version_machines` by the core migration so the plugin chain
+resumes seamlessly on existing installs. The plugin registry auto-migrates an
+`equipment` key to `machines` on load.
+
+Historical migrations and accepted ADRs are not rewritten; old ids and ADR-005
+wording remain as history.
+
+## Consequences
+
+- Upgrading instances run `flask db upgrade` then `flask plugin upgrade-all`,
+  same as every deploy; both migrations are idempotent.
+- `/api/equipment` and `equipmentApi` cease to exist - a breaking change made
+  while there is nobody to break. After contract 1.0 this class of rename
+  would be a major-version event; this is the last cheap moment.
+- The "Machine Types" settings card becomes "Model Types" and finally says
+  what it does; the machines plugin's subtype card owns the machine-types name.
+- Contributors stop translating between UI vocabulary and code vocabulary.
diff --git a/docs/adr/README.md b/docs/adr/README.md
index f690596..610d41f 100644
--- a/docs/adr/README.md
+++ b/docs/adr/README.md
@@ -23,6 +23,7 @@ Each ADR captures a single architectural decision: the context, the decision its
 | [008](ADR-008-plugin-migration-ownership.md) | Plugin migration ownership (per-plugin chains) | ACCEPTED |
 | [009](ADR-009-frontend-plugin-gating.md) | Frontend plugin route gating | ACCEPTED |
 | [010](ADR-010-frontend-plugin-hooks.md) | Frontend plugin hook contract | PROPOSED |
+| [011](ADR-011-machines-rename.md) | Machines rename + modeltypes retyping | ACCEPTED |
 
 ## Authoring