What kind of architecture does the team use/prefer? MVVM or other? Is SwiftUI designed to work with any specific architecture?

What is the recommended way to pass data from child to parent view in SwiftUI? I understand this could be done using PreferenceKey, but I wonder what alternatives there are and what is recommended?

I noticed that a lot of sample code uses var instead of let for read only properties of Views. Is there any difference? I usually use let in my structs unless I explicitly need mutability.

Are there any recommendations to display list's with large datasets with SwiftUI?