How do you approach choosing an architecture for a project?

The choice of architecture is determined by the scale, complexity of the project, team, and requirements for testability and maintainability.

The main types of architectures I consider for Flutter projects:

• MVC (Model-View-Controller): Simple, but less suitable for complex UI due to tightly coupled components.
• MVP (Model-View-Presenter): Improves responsibility separation compared to MVC, with the Presenter interacting with the View through an interface.
• MVVM (Model-View-ViewModel): Widely used in Flutter. The ViewModel contains logic and state, and the View subscribes to changes. Well-suited for testing.
• BLoC (Business Logic Component): Stream-based approach for managing state and business logic. Ensures clean code, good testability, and scalability.
• Cubit: A simplified version of BLoC, does not use Streams for input, only for output (State). Easier to use for simple scenarios.
• Provider: A convenient, flexible, and simple package for state management and dependencies. Often used in combination with other patterns or alone for simple applications.

Selection process:

1. Requirements analysis: Assess UI complexity, business logic, offline work necessity, integration with external services.
2. Scalability and maintainability: How easily the functionality can be expanded and changes made in the future.
3. Testability: How easily unit and widget tests can be written.
4. Team experience: Choosing an architecture that the team has experience with will speed up development.
5. Project size: For small projects, Provider or Cubit/simple architecture may suffice. For larger and more complex projects, BLoC or MVVM are more preferable.

Example of combining approaches for a medium/complex project:

• Global state management: Provider or Riverpod (as an alternative to Provider with compile-time safety).
• Feature-specific state management: BLoC or Cubit for complex business logic within individual modules.
• Dependency Injection: GetIt or Injectable for managing dependencies.
• Routing: go_router or auto_route.

Important aspect: Adaptability. The architecture should be flexible enough to be adapted or combined with different approaches if necessary. The main thing is to follow principles of clean code, such as SOLID, and maintain clear separation of responsibilities.