src/
├── Domain/              # Innermost: Business Logic (Pure TS)
│   ├── Entities/        # Core business objects
│   ├── ValueObjects/    # Immutables (Email, Price)
│   ├── Interfaces/      # Repository/Service contracts
│   └── Exceptions/      # Domain-specific errors
├── Application/         # Orchestration Layer
│   ├── UseCases/        # Application-specific logic
│   ├── DTOs/            # Data Transfer Objects
│   └── Interfaces/      # External service contracts
├── Infrastructure/      # External Layer (Implementations)
│   ├── Persistence/     # Repositories (Atlas)
│   ├── ExternalServices/# Mail, Payment gateways
│   └── Providers/       # Service Providers
└── Interface/           # Delivery Layer
    ├── Http/Controllers/# HTTP Entry points
    └── Presenters/      # Response formatters

📜 Layer Rules

1. The Dependency Rule

Inner cannot see Outer. Domain must NOT import from Application or Infrastructure.
Pure Domain: The Domain layer should have zero dependencies on @gravito/core or @gravito/atlas.

2. Entities & Value Objects

Entity: Has an ID. Mutability allowed via domain methods.
Value Object: Immutable. No identity. Two are equal if values are equal.

🏗️ Code Blueprints

Use Case Pattern

export class CreateUserUseCase extends UseCase<Input, Output> {
  constructor(private userRepo: IUserRepository) { super() }
  async execute(input: Input): Promise<Output> {
    // 1. Domain logic...
    // 2. Persist...
    // 3. Return DTO...
  }
}

🚀 Workflow (SOP)

Entities: Define the core state in src/Domain/Entities/.
Interfaces: Define the persistence contract in src/Domain/Interfaces/.
Use Cases: Implement the business action in src/Application/UseCases/.
Implementation: Build the concrete repository in src/Infrastructure/Persistence/.
Wiring: Bind the Interface to the Implementation in a Service Provider.
Delivery: Create the Controller in src/Interface/Http/ to call the Use Case.

clean-architect

Clean Architecture Master

🏢 Directory Structure (Strict Isolation)