How does Rails handle large-scale distributed system design using hexagonal (ports and adapters) architecture?

Rails can implement hexagonal architecture by isolating domain logic from frameworks using ports (interfaces) and adapters (implementations).

Hexagonal architecture (ports and adapters) restructures Rails applications so that the core domain logic is independent of Rails itself. In this model, controllers, ActiveRecord, and external services become adapters, while business logic is placed in pure Ruby services. Ports define contracts for input/output operations. This improves testability, scalability, and allows swapping infrastructure components (databases, APIs) without changing core logic.