MVVM seemed simple. Then you added ten MutableStateFlow properties to your ViewModel. MVI promised purity. Then you wrote a middleware for side effects.

There’s a better way.

The Problem With MVVM

A typical ViewModel looks like this:

class ProfileViewModel : ViewModel () { val name = MutableStateFlow ( "" ) val email = MutableStateFlow ( "" ) val isLoading = MutableStateFlow ( false ) val error = MutableStateFlow < String ?>( null )

fun updateProfile ( name : String ) { viewModelScope . launch { isLoading . value = true try { profileService . update ( name ) this @ProfileViewModel . name . value = name } catch ( e : Exception ) { error . value = e . message } finally { isLoading . value = false } } } }

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Five mutable properties. Loading state scattered across three places. Error handling duplicated in every method.…