lib/modules/feature/
├── data/           # DTOs, datasources, repository impl
├── domain/         # Entities, contracts, use cases
└── presentation/   # Pages, widgets, providers

// Always use const
const MyWidget({super.key});

// Extract widgets, not methods
class _UserAvatar extends StatelessWidget { ... }

// Use freezed for models
@freezed
class User with _$User {
  const factory User({required String id}) = _User;
}

// Selective rebuilds
BlocSelector<AuthBloc, AuthState, bool>(
  selector: (state) => state is AuthLoading,
  builder: (context, isLoading) => ...,
)

// BLoC test
blocTest<AuthBloc, AuthState>(
  'emits [Loading, Success] on login',
  build: () => AuthBloc(useCase: mockUseCase),
  act: (bloc) => bloc.add(LoginRequested()),
  expect: () => [AuthLoading(), AuthSuccess(user)],
);

dart run build_runner build --delete-conflicting-outputs
flutter test --coverage
flutter analyze