Session 6 — ADRs (Architectural Decision Records)

Goal: Verify all 30 ADRs are still valid. Flag any that need superseding or updating. Estimated time: 60 min

All ADRs live in docs/3-resources/decisions/. No index page exists — this session serves as one.

By Domain

Tenant & Auth (read first)

ADR	Title
ADR-003	Tenant Provisioning
ADR-004	Tenant Isolation Strategy
ADR-005	Multi-Tenant JWT Session

Commerce & Pricing

ADR	Title
ADR-001	Boarding Point Strategy
ADR-006	Costing/Pricing Separation
ADR-009	Booking Confirmed Trigger
ADR-010	Input/Output VO Separation
ADR-011	Input Rule Snapshotting
ADR-012	TOMS Tax Deferral
ADR-013	Seat Hold TTL Alignment
ADR-014	Ticket Issuance Trigger
ADR-015	Tax Ledger Entry Cardinality
ADR-030	Subscription Tier Gating

Operations

ADR	Title
ADR-007	Crew/Fleet/Subcontracting
ADR-008	Vehicle Maintenance Ownership
ADR-016	Incident Lifecycle State Machine
ADR-017	Offline Sync Protocol
ADR-018	ServiceLeg Creation Ownership
ADR-019	Change Events / Audit Trail
ADR-021	Customer Intelligence Context

Infrastructure

ADR	Title
ADR-022	Ubicloud Postgres Cutover
ADR-023	Swarm Quorum Topology
ADR-024	Swarm LB Strategy
ADR-025	Swarm Manager Failover DNS
ADR-027	Cardinality Budget Contract
ADR-028	GDPR TTL Retention
ADR-029	Secrets and Encryption
ADR-031	Immutable Infrastructure Policy

Governance

ADR	Title
ADR-020	Agentic Company Governance

🔍 What to Validate

• [ ] ADR-026 is missing (jumps 025 → 027). Was it deleted or never created?
• [ ] ADRs are supposed to be immutable. If any decision has changed, it needs a new ADR that supersedes the old one — check for any that feel outdated.
• [ ] ADR-012 defers TOMS tax to Phase 3. Is that still the plan?
• [ ] ADR-017 (offline sync) — does offline-sync-protocol.md reflect the decision?
• [ ] ADR-020 + ADR-021 describe future contexts — are they still aligned with the current vision?
• [ ] ADR-030 (subscription gating) — does it match PRODUCT_payments-and-billing.md?

Findings