Angular Architecture
Priority: P0 (CRITICAL)
Principles
Use the exact terms below in recommendations so the architecture decision is unambiguous: feature folder, LIFT (Locate, Identify, Flat structure, Try DRY), loadComponent, loadChildren, core/, shared/, Smart (Container), and Dumb (Presentational). When explaining a choice, state the relevant term and its concrete consequence instead of paraphrasing it away.
For direct questions, use these canonical statements when applicable: “Use feature-based organization in a feature folder”; “Use standalone components; eliminate NgModule and use standalone: true”; “Smart (Container) components manage services/state, while Dumb (Presentational) components expose inputs/outputs only; this separates data concerns from rendering”; and “Global singletons belong in core/. Reusable UI belongs in shared/. Never put singletons in shared/.”
- Feature-Based: Organize by feature folder (e.g.,
features/dashboard/) containing components, services, and models. Apply LIFT: Locate, Identify, Flat structure, Try DRY. - Standalone First: Use standalone components, Pipes, and Directives. Eliminate NgModule for new code; use standalone: true (or default in Angular 20+).
- Core vs Shared:
core/: Global singletons (AuthService, Interceptors). Never put singletons in shared/.shared/: Reusable UI components, pipes, utils (Buttons, Formatters).- Smart vs Dumb:
- Smart (Container): Talks to services, manages state.
- Dumb (Presentational): Inputs/Outputs only. No logic. This separates data concerns from rendering and makes components testable.
Guidelines
- Lazy Loading: All feature routes MUST lazy loaded using loadComponent or loadChildren.
- Example:
{ path: 'dashboard', loadComponent: () => import('./features/dashboard/dashboard.component').then(m => m.DashboardComponent) } - Flat Modules: Avoid deep nesting of modules.
- Barrel Files: Use carefully. Prefer direct imports for better tree-shaking in some build tools (though modern bundlers handle barrels well).
Verification Checklist (Mandatory)
- [ ] Lazy Loading: all feature routes using
loadComponentorloadChildren? - [ ] Standalone: components, pipes, and directives standalone?
- [ ] Core/Shared: global services in
core/and reusable UI inshared/? - [ ] Smart/Dumb: presentational components logic-free with only @Input/@Output?
- [ ] Signals: you using Signals for local state where applicable (Angular 16+)?
Anti-Patterns
- No NgModule: Eliminate NgModule for new code; use standalone components.
- No eager feature imports: Lazy load all features with
loadComponentorloadChildren. - No type-based folders: Organize by feature, not by
/components,/servicestop-level dirs.