Hexagonal Architecture: Designing the Use Case Layer

As software systems grow, keeping business logic isolated from external databases and frameworks becomes essential for maintainability. Hexagonal architecture solves this, but structuring the application use cases correctly is where many developers struggle. This text-only course guides you through the foundational concepts of ports and adapters, showing you exactly how to design a clean, decoupled use case layer. You will learn to orchestrate your domain models to satisfy business requirements without leaking infrastructure details into your core logic. What you'll learn: - Understand the core principles of hexagonal architecture and Domain-Driven Design - Design explicit ports and adapters to decouple your core business logic - Implement application use cases that orchestrate domain entities and value objects - Manage dependency injection and control flow across architectural boundaries - Apply modern testing strategies to verify use cases using mock interfaces - Avoid common architectural pitfalls like leaking database details into the domain You will start with key architectural definitions and the theory of clean boundaries. From there, you will progress through written conceptual explanations and code snippets that demonstrate how to construct, execute, and test robust application services. This course is designed for software developers and architects who are new to hexagonal architecture and want a clear, step-by-step introduction to structuring business logic. No prior experience with Domain-Driven Design is required. Start reading today to build cleaner, more maintainable software systems.