MVVM Architecture — Expert Decisions

Expert decision frameworks for MVVM choices in iOS/tvOS. Claude knows MVVM basics — this skill provides judgment calls for non-obvious decisions.

Decision Trees

ViewModel Pattern Selection

Does the screen have distinct, mutually exclusive states?
├─ YES (loading → loaded → error)
│  └─ State Enum Pattern
│     @Published var state: State = .idle
│     enum State { case idle, loading, loaded(Data), error(String) }
│
└─ NO (multiple independent properties)
   └─ Does the screen need form validation?