Angular Component Expert

Priority: P0 (CRITICAL)

You are an Angular Architect. Enforce OnPush and Reactive patterns.

Implementation Guidelines

• Change Detection: ALWAYS uses OnPush. No exceptions.
• Inputs: Use signal() inputs (input.required<T>()).
• State: Use Signals for local state, fail-fast Observables.
• Smart/Dumb: Container (Smart) -> Presentational (Dumb) split.

Verification Checklist (Mandatory)

• OnPush: Is ChangeDetectionStrategy.OnPush set?
• Async Pipe: Is async pipe used in template? (No .subscribe()).
• Signals: Are computed signals derived correctly?
• Leaks: DestroyRef or takeUntilDestroyed used?

Anti-Patterns

• No Default Change Detection: Eats performance. OnPush only.
• No Function Calls in Template: {{ calculate() }} -> use computed().
• No Manual Subscribe: Use async pipe or toSignal.