ADR-008: Vehicle Maintenance Schema Ownership

Status: ✅ Accepted Date: 2026-04-09 Triggered by: Level 2 Audit — Crew & Fleet Management (Findings M1, M2)

Context

The Level 2 Audit identified vehicle maintenance tracking as a High-priority gap in PRODUCT_schema-feature-gaps.md §1. Two types of maintenance exist in DACH bus operations:

1. Scheduled regulatory inspections — HU (Hauptuntersuchung), SP (Sicherheitsprüfung), tachograph calibration, UVV. These are known in advance, tied to the vehicle's lifecycle, and determine whether a vehicle is legally roadworthy.
2. Unscheduled field issues — Mechanical problems discovered during operation (cracked mirror, engine warning light). Drivers report these via IssueReport (Operations).

The feature gaps document places maintenance in "Operations / Backoffice" without resolving ownership. The dispatch board spec (dispatch-board.md) initially listed vehicle_inspections under the Operations schema.

Decision

Split ownership based on data lifecycle:

• Backoffice owns vehicle_inspections — scheduled regulatory deadlines are master data tied to the vehicle's identity and lifecycle. Dispatchers manage these as part of fleet administration.
• Operations owns issue_reports (already exists) — unscheduled field maintenance stays in the execution layer where drivers create it.
• A cross-context domain event VehicleMaintenanceRequired (Operations → Backoffice) bridges the gap: when a driver flags maintenance_urgency: IMMEDIATE on an IssueReport, Backoffice creates a corresponding VehicleInspection entry.

Consequences

• vehicle_inspections lives in schema: backoffice. This ADR updates the dispatch board data dependencies table accordingly.
• issue_reports gains a maintenance_urgency field (NONE, IMMEDIATE, SCHEDULED) for cross-context escalation.
• VehicleMaintenanceRequired domain event added to the context map (Operations → Backoffice).
• Safety-critical overdue inspections (HU, SP) automatically set blocks_dispatch = true, making them hard dispatch blocks (not just warnings).
• Hasura scheduled triggers drive QualificationExpiring and VehicleInspectionOverdue notifications (Backoffice → Communications) for proactive manager alerts.