architecture

name	architecture
description	Clean Architecture (Uncle Bob) guide for this project. Use when creating modules, entities, use cases, presenters, controllers, gateways, guards, services. Contains tactical patterns and structure conventions.

Clean Architecture - Tactical Guide

Persona

Read .claude/roles/architect.md — adopt this profile and follow all its rules.

Activation

This skill activates for any creation or modification of architectural components:

• Entities, Use Cases, Presenters
• Controllers, Gateways, Guards
• Services
• Module structure

Core Principle

"The architecture should scream the intent of the system." — Uncle Bob

┌─────────────────────────────────────┐
│       Interface Adapters            │  ← Controllers, Presenters, Gateways
├─────────────────────────────────────┤
│           Use Cases                 │  ← Application Business Rules
├─────────────────────────────────────┤
│            Entities                 │  ← Enterprise Business Rules
└─────────────────────────────────────┘

Dependency Rule: Dependencies point inward. The domain knows nothing about infrastructure.

---

Module Structure

src/
├── entities/
│   └── <entity>/
│       ├── <entity>.ts              # Entity + business logic
│       ├── <entity>.schema.ts       # Zod schema
│       ├── <entity>.guard.ts        # Boundary validation
│       └── <entity>.gateway.ts      # Interface (port)
├── usecases/
│   └── <action><Entity>.usecase.ts
├── interface-adapters/
│   ├── controllers/
│   │   ├── webhook/
│   │   │   └── <platform>.controller.ts
│   │   ├── http/
│   │   │   └── <feature>.routes.ts
│   │   └── mcp/
│   │       └── <action>.handler.ts
│   ├── presenters/
│   │   └── <feature>.presenter.ts
│   ├── gateways/
│   │   └── <entity>.<source>.gateway.ts
│   └── adapters/
│       └── <platform>.adapter.ts
├── shared/
│   └── foundation/
│       ├── usecase.base.ts
│       ├── guard.base.ts
│       ├── gateway.base.ts
│       └── presenter.base.ts
└── tests/
    ├── units/
    ├── factories/
    ├── stubs/
    └── mocks/

---

Components

Entity

Pure business logic, independent of any framework.

// entities/review/reviewScore.valueObject.ts
export class ReviewScore {
  private constructor(private readonly props: ReviewScoreProps) {}

  static create(props: ReviewScoreProps): ReviewScore {
    const validated = ReviewScoreSchema.parse(props);
    return new ReviewScore(validated);
  }

  get blocking(): number {
    return this.props.blocking;
  }

  get severity(): Severity {
    if (this.blocking > 0) return 'critical';
    if (this.warnings > 0) return 'warning';
    if (this.suggestions > 0) return 'info';
    return 'clean';
  }

  get hasBlockingIssues(): boolean {
    return this.blocking > 0;
  }
}

Use Case

Orchestrates a business action. One use case = one user intention.

// usecases/triggerReview.usecase.ts
export function triggerReview(
  params: TriggerReviewParams,
  deps: TriggerReviewDependencies
): TriggerReviewResult {
  const { queuePort, reviewRequestTrackingGateway, logger } = deps;

  const jobId = queuePort.createJobId(params.platform, params.projectPath, params.reviewRequestNumber);

  if (queuePort.hasActiveJob(jobId)) {
    return { status: 'deduplicated', reason: 'Review already in progress' };
  }

  const enqueued = queuePort.enqueue(job);
  if (!enqueued) {
    return { status: 'failed', reason: 'Queue full or job rejected' };
  }

  reviewRequestTrackingGateway.recordPush(params.localPath, params.reviewRequestNumber, params.platform);
  return { status: 'success', jobId };
}

Presenter

Transforms business data into a ViewModel. Contains ALL presentation logic.

// interface-adapters/presenters/reviewList.presenter.ts
export class ReviewListPresenter {
  constructor(private jobPresenter: JobStatusPresenter) {}

  present(active: JobStatus[], recent: JobStatus[]): ReviewListViewModel {
    const activeJobs = active.map(job => this.jobPresenter.present(job));
    const recentJobs = recent.map(job => this.jobPresenter.present(job));
    const totalCount = activeJobs.length + recentJobs.length;

    return {
      activeJobs,
      recentJobs,
      totalCount,
      isEmpty: totalCount === 0,
      emptyMessage: 'No active reviews',
    };
  }
}

ViewModel

Simple data structure. Formatted strings, UI booleans. Defined with a TypeScript interface.

// interface-adapters/presenters/reviewList.presenter.ts
export interface ReviewListViewModel {
  activeJobs: JobStatusViewModel[];
  recentJobs: JobStatusViewModel[];
  activeCount: number;
  recentCount: number;
  totalCount: number;
  isEmpty: boolean;
  emptyMessage: string;
}

Controller

Orchestrates Use Case + Presenter. Entry point for an action.

// interface-adapters/controllers/webhook/github.controller.ts
export async function handleGitHubWebhook(
  request: FastifyRequest,
  reply: FastifyReply,
  logger: Logger,
  trackingGateway: ReviewRequestTrackingGateway,
  deps: GitHubWebhookDependencies
): Promise<void> {
  const { trackAssignment, recordCompletion } = deps;

  const verification = verifyGitHubSignature(request);
  if (!verification.valid) {
    reply.status(401).send({ error: verification.error });
    return;
  }

  // Orchestrate use cases...
}

Gateway

Interface (port) in entities, implementation in interface-adapters.

// entities/reviewContext/reviewContext.gateway.ts (CONTRACT)
export interface ReviewContextGateway {
  create(input: CreateReviewContextInput): CreateReviewContextResult;
  read(localPath: string, mergeRequestId: string): ReviewContext | null;
  exists(localPath: string, mergeRequestId: string): boolean;
  appendAction(localPath: string, mergeRequestId: string, action: ReviewContextAction): UpdateResult;
}

// interface-adapters/gateways/reviewContext.fileSystem.gateway.ts (IMPLEMENTATION)
export class ReviewContextFileSystemGateway implements ReviewContextGateway {
  read(localPath: string, mergeRequestId: string): ReviewContext | null {
    const filePath = this.getFilePath(localPath, mergeRequestId);
    if (!existsSync(filePath)) return null;
    const content = readFileSync(filePath, 'utf-8');
    return JSON.parse(content) as ReviewContext;
  }
}

Guard

Boundary validation with Zod.

// entities/reviewContext/reviewContextAction.guard.ts
export const reviewContextActionGuard = createGuard(reviewContextActionSchema);

export function parseReviewContextAction(data: unknown): ReviewContextAction {
  return reviewContextActionGuard.parse(data);
}

export function isValidReviewContextAction(data: unknown): data is ReviewContextAction {
  return reviewContextActionGuard.safeParse(data).success;
}

export function parseReviewContextActions(data: unknown): ReviewContextAction[] {
  return reviewContextActionsGuard.parse(data);
}

Service

Utilities injected via Dependencies.

Scope	Location
Cross-context	shared/services/
Specific to bounded context	interface-adapters/gateways/ or services/

---

Dependency Injection

Via composition root in src/main/routes.ts. See references.md for details.

// main/routes.ts — the "dirty" component (Uncle Bob Ch. 26)
app.post('/webhooks/github', async (request, reply) => {
  await handleGitHubWebhook(request, reply, deps.logger, trackingGw, {
    reviewContextGateway: deps.reviewContextGateway,
    threadFetchGateway: new GitHubThreadFetchGateway(defaultGitHubExecutor),
    trackAssignment: new TrackAssignmentUseCase(trackingGw),
    recordCompletion: new RecordReviewCompletionUseCase(trackingGw),
  });
});

---

Test Doubles

tests/
├── stubs/
│   └── reviewContextGateway.stub.ts    # Happy path
├── factories/
│   └── reviewContext.factory.ts         # Test data creation
└── mocks/

See examples.md for concrete examples.

---

Anti-patterns to Avoid

• No business logic in Controllers
• No presentation logic in Use Cases
• No infrastructure awareness in Entities
• No outward-pointing dependencies
• No as Type assertions — use guards with Zod