10. Quality Requirements¶

The nineteen architectural drivers in architecture/architecture.md §Architectural Drivers serve as Finnest's quality-attribute tree. Each maps to measurable acceptance criteria.

Top-tier quality attributes¶

Attribute	Target	Verified by
Security (IRAP OFFICIAL:Sensitive)	ISM controls met; session ≤ 15 min; FIDO2 mandatory	IRAP assessor audit (Week 44)
Compliance	Non-compliant workers blocked synchronously at write in 5 domains	ADR-011-F; integration tests
Multi-tenant isolation	`org_id` leakage → P0 incident; agents never reused across tenants	`architecture_test` suite (STORY-F-007)
AI cost ceiling	≥70 % of queries served at $0; per-org circuit-breaker at configured ceiling	BudgetGuard instrumentation, weekly cost digest
Disaster recovery	RPO ≤ 15 min, RTO ≤ 4 hr	Multi-AZ RDS + cross-region snapshot; rehearsed quarterly
Audit immutability	7-year retention; hash chain unbroken	Trigger-enforced; audit probe (STORY-F-016)
Financial precision	Zero floats in pay / billing / margin / awards	Credo custom rule + code review
Accessibility	WCAG 2.1 AA across all screens	Axe-core in CI; manual audit pre-GA

Attribute	Target
Performance — health probe	`/health` < 50 ms in-process
Performance — readiness probe	`/ready` ≤ 150 ms including `SELECT 1`
Performance — p95 page render	< 500 ms commercial, < 1000 ms IRAP (proxy overhead)
Observability	100 % request tracing with correlation ID; structured JSON logs
Deployability	Zero-downtime deploy; any branch → integration host in ≤ 10 min
Test coverage	≥ 80 % for tier-1 apps; ≥ 70 % for tier-2+; branch coverage on compliance gates

Writing these down explicitly prevents accidental over-engineering:

Not a high-throughput write system. A large org has thousands of shift writes/day, not thousands per second. No sharding.
Not a global system. Single-region Australian deploy. No geo-routing.
Not a streaming analytics platform. Events are for audit and cross- domain comms, not real-time dashboards. Dashboards query materialised views.
Not a general-purpose developer platform. No public API in Phase 0; MCP tools are internal-use-only.

Every quality target has at least one enforcement mechanism from this list:

CI gate — build fails if violated (format, credo, sobelow, dialyzer, tests, coverage)
Architecture test — architecture_test suite; compile-time contract checks via the Boundary library (STORY-F-002)
Runtime probe — /health, /ready, plus per-domain MCP tool health checks
Peer review — the 42 Commandments (ADR-013-F)
Periodic audit — compliance assessor (IRAP), accessibility audit (internal)

See 10-GUARDRAILS.md for the full enforcement catalogue (177 individual guardrails).