Chapter 16: Independence
A good architecture supports independent developability, deployability, and operability. Martin explains the use-case, operational, and deployment decoupling modes and why the monolith-vs-microservices decision can and should be deferred.
Chapters 17–20: Boundaries, Business Rules & Policy
Boundaries separate software elements and restrict knowledge between them. This section covers drawing lines between components, anatomy of boundaries, policy levels, entities, and use cases — the core of Clean Architecture.