flutter-apply-architecture-best-practices

To structure a Flutter app for scalability, enforce a strict separation of concerns between UI, domain, and data layers using the MVVM pattern. This approach decouples ViewModels and Repositories, ensuring testable code as project complexity grows.

Refactoring legacy Flutter spaghetti code is best achieved by migrating to a feature-based organization with layered architecture. Implement repository-based data access and dependency injection to decouple tangled UI and business logic.

The repository pattern works with MVVM by handling data access in the repository layer, while ViewModels manage domain logic and UI state. This ensures consistent dependency injection and keeps data layers fully testable across features.

Yes, you need dependency injection to maintain a testable code structure in Flutter. It enables strict separation of concerns by injecting services and repositories into ViewModels, ensuring each feature module remains decoupled.

You can use this layered architecture approach for both existing Flutter features and new projects. It is designed to help refactor legacy code modules and structure new features by applying consistent dependency injection and MVVM patterns.