Domain-Driven Design (DDD): Tactical Building Blocks & Review

Tactical DDD focuses on the technical implementation of rich domain models within a single Bounded Context. While Strategic DDD answers "What to build and where?", Tactical DDD answers "How do we model this in code?"

"The heart of DDD is the Domain Model itself." — Eric Evans

🧱 Building Blocks Reference

1. Entity

Definition: An object with a unique identity that persists over time. Two entities with the same ID are the same entity, even if their attributes differ.

Characteristics:

• Has a globally unique, stable identity (UUID, auto-increment, natural key)
• Mutable state (attributes can change)
• Identity equality: a.id == b.id means a == b
• Encapsulates business logic (not just data + getters/setters)