Hexagonal Architecture: Robust Software With Interfaces Instead of Layers

We all know this situation: The older and larger an application becomes, the more complex and expensive it is to extend and maintain. The widely used layered architecture is insufficient as a solution: Direct and indirect dependencies from all layers to the database and other infrastructure components often lead to blurred layer boundaries and a tight coupling of technical and business code.

Hexagonal architecture places business logic at the center and isolates technical details behind interfaces (ports) using adapters. This allows business and technical code to be developed and tested independently of each other.

Starting with the goals of a software architecture and a critical look at layered architecture, we take an in-depth look at hexagonal architecture. You’ll learn how the Dependency Rule ensures that there are no dependencies from business code to technical code—and how the application core can still access infrastructure. Does hexagonal architecture fulfill the goals of a software architecture? What challenges does it bring? How does it differ from Onion and Clean Architecture, and what synergies emerge when combined with microservices and Domain-Driven Design?

Armed with new knowledge, you’ll be able to improve the quality and longevity of your software projects and respond more quickly to new requirements in the future.

👉 Links and slides
https://www.happycoders.eu/hex-arch-l...

👉 All articles in the series:
What is Hexagonal Architecture? https://www.happycoders.eu/software-c...
Hexagonal Architecture with Java: https://www.happycoders.eu/software-c...
Adding a Database Adapter: https://www.happycoders.eu/software-c...
Hexagonal Architecture with Quarkus: https://www.happycoders.eu/software-c...
Hexagonal Architecture with Spring Boot: https://www.happycoders.eu/software-c...

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