Request contracts validate input AND map external API names onto domain entities
Domain-Driven Design architecture patterns and conventions for this project
Roar::Decorator representers that turn domain entities into JSON
Presentation layer serializes domain entities to wire formats (JSON, etc.)
Repository pattern for translating between ORM rows and domain entities
How orm/ and repositories/ split responsibility in app/infrastructure/database/
When to use Dry::Struct DTO entities vs. plain Ruby class entities in domain/entities/
Thin Sequel::Model wrappers — no business logic, no domain knowledge