Domain Modeling

These standards govern how a domain concept becomes a type: where behaviour lives, how invariants are protected, and how to avoid the anemic, flag-driven models that push logic into services and callers instead of the type itself. Apply them whenever defining or reworking an entity, aggregate, or value object.

• Avoid Anemic Domain Models
• Avoid the Combinatorial Explosion Trap From Anemic Models
• Build External API Queries With a Lightweight Query Specification
• Clean Architecture Use Cases
• Eliminate Data Clumps with Value Objects
• Enforce Invariants in Constructors via Factory Methods
• Express Business Rules as Composable, Injectable Rule Objects
• Immutable Domain Models
• Model EF Core Aggregates as Immutable Types
• Push Type-Specific Branching Into Polymorphic Methods
• Refactor Anemic State-Bag Models
• Replace Boolean Status Flags With Closed Type Hierarchies
• Use Records as Functional Values, Not Objects With Hidden State