4.Programming Patterns

Configuring constructors through composable option functions, especially in Go APIs.

Using function values to satisfy small behavioral contracts and inject behavior without heavyweight objects.

Persisting domain changes as an append-only event history and rebuilding state through replay/projections.

Decoupling event publishers and subscribers while handling delivery, ordering, replay, and failure semantics.

Decoupling work generation from processing with queues, bounded capacity, backpressure, and worker concurrency.