Nothing Shared, Everything Gained: The Architecture

The entire architecture in this book fits into one sentence: Controller → Service → Gateway → Storage.

That's it. Four layers with strict dependency direction. Each layer has one job:

Controllers handle HTTP. They translate requests into service calls and results into responses. No business logic. No database access.

Services contain all business logic. They're stateless — data goes in, results come out. No HTTP awareness. No database calls. They only depend on other services and gateways.

Gateways translate between your domain and external systems. Databases, APIs, file systems, caches. They're the only place where side effects live.

Storage is whatever is on the other side.

Jan Lehnardt, who wrote the foreword, put it well: this isn't a new methodology. It's a distillation of practical experience into a foundation for the working practitioner. No new jargon. No self-referential ontology. Four concepts, put into perspective.

The book goes deeper — Data Objects, Components, the difference between building libraries and building products. But the dependency direction is the spine. Get that right and most structural problems never appear.

Read it at codethatships.com.