ooad-architect

OOAD Architect — Design

Transforms validated RE into architecture: C4/UML, RDD→GRASP responsibility assignment, data model, GoF selection, Clean 4 Layers layout with ADR-MADR. See references/ooad-vocabulary.md.

Preconditions

• docs/02-requirements/ baselined (SRS or backlog).
• docs/agents/workflow.md + docs/agents/architecture.md.
• CONTEXT.md + conceptual-model.puml exist.

Process

1. Review RE

Read docs/02-requirements/SRS.md or backlog/US-*.md + UC-*.md + RTM.csv + conceptual-model.puml + context.puml.

Done when: every FR/UC/US is mapped to a conceptual class in RTM.csv and all NFRs that drive architecture are highlighted.

2. Propose architecture — do not proceed without human approval

Propose:

• Style: Clean 4 Layers (Entities → Use Cases → Interface Adapters → Frameworks) default; alternatives MVC (Reenskaug) or Hexagonal (Cockburn) per docs/agents/architecture.md.
• C4 (Simon Brown): L1 Context, L2 Container, L3 Component (per size).
• UML (OMG): class-diagram.puml, sequence-diagram.puml per critical UC, state-diagram.puml if applicable.
• Data model: ER → relational schema + normalization.
• GoF (Gamma et al.): selection matrix Factory/Singleton | Adapter/Decorator/Proxy/Composite | Observer/Strategy/State/Command — justify each (problem solved, discarded alternative, and the tradeoff accepted — GoF's Mission is named solutions with evaluated consequences, not fashion).
• Responsibility assignment — RDD → GRASP (Wirfs-Brock → Larman): start from docs/02-requirements/crc-cards.md; map every sequence message to a class operation and cite one GRASP pattern per mapping (default: Information Expert; creation: Creator; system events: Controller = UseCase, never UI/Framework; variation points: Protected Variations + the GoF that implements it; no-fit helpers: Pure Fabrication with cohesion rationale). Each mapping states the pattern's Mission: from references/ooad-vocabulary.md (one line — why this owner, not another). Reject God-controllers and feature-envy assignments (Low Coupling / High Cohesion check).
• Modules/packages: responsibility per package.
• Dependency Rule (Martin): imports point inward (Frameworks → Adapters → UseCases → Entities); flag violations.

Done when: user explicitly approves style, C4 levels, responsibility assignment (CRC→GRASP map), and GoF choices (ask: architecture OK? preferred pattern? add/remove?).

3. Produce artifacts (after approval)

docs/03-architecture/
├── c4-context.puml / c4-container.puml
├── class-diagram.puml       (→ .svg)
├── sequence-diagram-UC-001.puml
├── data-model-er.puml
├── adrs/
│   ├── 0001-clean-4-layer-architecture.md  (MADR — Starke)
│   ├── 0002-strategy-for-rules.md
│   └── 0003-orm-vs-sql.md
└── README.md

MADR format: Context → Decision → Consequences → Alternatives. Templates: templates/adr-madr.md, templates/c4.puml, templates/class-diagram.puml. Pre-render plantuml -tsvg docs/03-architecture/*.puml.

Done when: all PUML render to SVG; each ADR has Context/Decision/Consequences/Alternatives and references a motivating NFR-xxx; every sequence message cites its GRASP pattern; RTM.csv updated with FR→Class→ADR.

4. Update scaffold README

Create/update docs/03-architecture/README.md embedding SVGs:

![C4 Context](c4-context.svg)
![Classes](class-diagram.svg)

Done when: README.md renders both SVGs and explains layer responsibilities in 3 lines per layer.

Reference

Verify

• [ ] C4/UML in PlantUML and SVGs rendered (plantuml -tsvg green)
• [ ] Every ADR has context/decision/consequences/alternatives; justified GoF matrix
• [ ] Every sequence-message → operation mapping cites a GRASP pattern plus its one-line Mission:; Controller is a UseCase; Protected Variations names its GoF
• [ ] No God-controller / feature envy (Low Coupling + High Cohesion reviewed against CRC cards)
• [ ] Dependency Rule respected; no Entities imports Frameworks
• [ ] Every class/module traced FR/UC/US → RTM.csv; NFR → ADR
• [ ] Human approval recorded

Gates by profile

• RUP (Jacobson): Elaboration delivers executable architectural baseline.
• Waterfall (Royce): Complete heavy SDD, detailed UML, signed.
• Agile: Just-enough C4 + ADR per significant decision, UML only as needed.

Rules

Do not invent a layer outside docs/agents/architecture.md without new ADR.