ADR-006: Enterprise Architecture Governance System

Status: Accepted
Date: 2026-07-04
Deciders: Architecture Review Board
Owner Platform: ZEP (PL-001)

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Context

ZAIXOS architecture freeze directive (v1.0) established stable platform ownership (PL-003–PL-006). Executable enforcement was partial: documentation existed, but machine-readable registries and automated product scanners were missing.

Evidence: docs/ARCHITECTURE_FREEZE_COMPLIANCE_REPORT.md, CI gaps in PL-004/PL-005, no ArchitectureGovernanceTest in products.

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Problem

Future contributors and Cursor sessions could introduce architectural drift (duplicate runtimes, product bypass of AgentTurnOrchestrator) without automated CI failure.

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Alternatives Considered

Alternative	Rejected because
New PL-007 governance platform	Violates freeze — no new platform
Markdown-only policy	Not executable; fails certification mandate
Per-repo duplicate rules	Drift between products; no single constitutional source
Remove legacy Dental orchestrators now	Breaking; not proven dead in tests

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Decision

Add additive governance layer in ZEP:

1. governance/architecture/ownership-registry.json — machine-readable ownership
2. governance/architecture/dependency-rules.json — executable dependency rules
3. validation/src/Governance/* — scanners and certification builder
4. validation/tests/ArchitectureGovernanceRegistryTest.php — registry integrity
5. Product ArchitectureGovernanceTest.php — PRD-000, PRD-001
6. PL-003 ArchitectureFreezeComplianceTest.php — platform freeze guards
7. ADR template + CI wiring

Grandfather transitional PRD-001 orchestrators via registry allowlist — no removal.

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Migration

None required. Existing code paths unchanged. CI adds blocking governance tests.

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Consequences

Positive

• CI fails on new ProviderGateway() in products
• Single ownership matrix validated automatically
• ADR process formalized

Negative

• PRD-001 legacy orchestrators remain until explicit removal milestone
• PL-004/PL-005 still lack dedicated CI workflows

Tests validating this decision

• ArchitectureGovernanceRegistryTest — 7/7 PASS
• ArchitectureGovernanceTest (PRD-000) — 5/5 PASS
• ArchitectureGovernanceTest (PRD-001) — 5/5 PASS
• ArchitectureFreezeComplianceTest (PL-003) — 7/7 PASS
• PL-003 architecture suite — 68/68 PASS