Injector Hierarchy (Module, Component)

6.4 Injector Hierarchy (module, component)

Angular has a hierarchical injector system:

• Root injector → app-wide services
• Module injector → module-scoped services
• Component injector → component & children

@Component({
  selector: "app-child",
  standalone: true,
  providers: [ChildService],
  template: `Child component`,
})
export class ChildComponent {
  constructor(private service: ChildService) {}
}

Note: Angular 21 retains hierarchical injectors. Signals do not change the hierarchy.