/docs/guides/requirements.md

Requirements Guide

Guide Origin: Official | ArcKit Version: [VERSION]

/arckit:requirements produces a single living document covering business, functional, non-functional, integration, and data requirements.

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Preparation

Artefact	Why it matters
Stakeholder analysis	Links goals and success criteria
Architecture principles	Provides constraints and validation gates
Risk register	Captures early compliance and delivery risks

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Command

/arckit:requirements Create requirements for <project>

Output: projects/<id>/ARC-<id>-REQ-v1.0.md.

Auto-versioning: Re-running this command when a document already exists automatically increments the version (minor for refreshed content, major for changed scope) instead of overwriting.

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Requirements Matrix

Type	Prefix	Purpose	Example prompts
Business	BR-###	Outcomes, KPIs, investment cases	“Reduce payment processing costs by 30%”
Functional	FR-###	User-facing features & flows	“Process card payments and provide receipts”
Non-Functional	NFR-<category>-###	Performance, security, availability, accessibility	“P95 latency < 500ms”, “WCAG 2.2 AA”
Integration	INT-###	Interfaces with external systems	“Integrate with HMRC PAYE API”
Data	DR-###	Entities, retention, PII	“Store audit logs for 7 years encrypted at rest”

For public sector projects, MoSCoW priorities are automatically assigned.

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Review Checklist

• Every requirement includes acceptance criteria and traceability references (stakeholder IDs, risks, principles).
• Conflicts and dependencies are called out (e.g. BR vs NFR tension).
• Regulatory obligations (TCoP, GDPR, WCAG, PCI-DSS) are captured explicitly.
• Integration requirements specify protocols, authentication, and error handling.
• Data requirements include lawful basis and retention aligned with DPIA outputs.

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After Generation

1. Workshop with stakeholders to confirm priorities and resolve conflicts.
2. Feed requirements into /arckit:sow, /arckit:diagram, /arckit:backlog.
3. For data mesh architectures, DR-xxx requirements inform /arckit:data-mesh-contract SLAs and quality rules.
4. Re-run the command whenever scope changes; commit deltas for audit.
5. Pair with /arckit:traceability to ensure design, tests, and operational artefacts stay aligned.