Non-Functional Requirements

Requirements

Non-functional requirements specify quality attributes, performance targets, scalability, security, reliability, and data integrity requirements.

1. Availability

NFR-AVL-001: The production system should target at least 99.5% monthly availability during the pilot
NFR-AVL-002: Planned maintenance should be communicated in advance
NFR-AVL-003: The application shall expose health and readiness endpoints

NFR-PERF-001: Normal list APIs should return within 2 seconds for the 95th percentile under expected pilot load
NFR-PERF-002: Requirement detail should load within 2 seconds for the 95th percentile
NFR-PERF-003: Version comparison should complete within 3 seconds for typical requirement sizes
NFR-PERF-004: Management dashboard queries should complete within 5 seconds for pilot-scale data
NFR-PERF-005: The system should support at least 100 concurrent pilot users

NFR-SCL-001: The architecture shall allow horizontal scaling of stateless API instances
NFR-SCL-002: Application sessions shall not depend on local server memory where avoidable
NFR-SCL-003: The data model shall support at least:

10,000 requirements
50,000 requirement versions
100,000 tasks
100,000 test executions
500,000 audit events
without redesigning core entities

NFR-SEC-001: All production traffic shall use TLS 1.2 or higher
NFR-SEC-002: Passwords shall be hashed using an approved adaptive algorithm (Argon2id or bcrypt)
NFR-SEC-003: Authorization shall be validated in the backend for every protected operation
NFR-SEC-004: Sensitive actions shall be audited with user, timestamp, and action details
NFR-SEC-005: The system shall protect against common OWASP application risks
NFR-SEC-006: Secrets shall not be stored in source control or configuration files
NFR-SEC-007: Authentication tokens shall have controlled expiry and refresh capabilities
NFR-SEC-008: File uploads shall be validated by size, type, and content policy

NFR-REL-001: Requirement approval and version creation shall occur inside a database transaction
NFR-REL-002: The system shall prevent multiple current approved versions for the same requirement
NFR-REL-003: Important mutation APIs should support safe retry or idempotency where appropriate
NFR-REL-004: Failed transactions shall not create partial audit or version state
NFR-REL-005: The system shall implement circuit breakers for external dependencies
NFR-REL-006: Retry logic shall implement exponential backoff with jitter

NFR-DATA-001: Foreign keys shall protect core relationships
NFR-DATA-002: Approved requirement versions shall be protected from update through database constraints
NFR-DATA-003: Status transitions shall be validated by business logic
NFR-DATA-004: Audit records shall be append-only and immutable
NFR-DATA-005: Current approved version uniqueness shall be enforced at the database level

NFR-MAINT-001: Code shall follow consistent style and naming conventions
NFR-MAINT-002: The system shall use structured logging for debugging and monitoring
NFR-MAINT-003: Database migrations shall be version-controlled and reversible
NFR-MAINT-004: Critical business logic shall have automated tests

NFR-DEPLOY-001: The system shall support OCI-compatible container deployment
NFR-DEPLOY-002: The system shall support local development without Kubernetes
NFR-DEPLOY-003: Configuration shall be externalized from code via environment variables or configuration files
NFR-DEPLOY-004: Zero-downtime deployments should be supported where practical

NFR-UX-001: The user interface shall be responsive and work on desktop and tablet devices
NFR-UX-002: The system shall follow accessibility best practices (WCAG 2.1 AA)
NFR-UX-003: Error messages shall be clear and actionable
NFR-UX-004: Role-based navigation shall hide unavailable actions

Next: Review the API Contract →