A very simple ViewModel first MVVM infrastructure that works equally well with WPF (requires MahApps.Metro) and UWP apps. Does not require a container or component framework, and does not prevent using one either.
A key feature is the IWindowManager to open new windows, display notifications, show dialogs. The API is consistent for both UWP and WPF applications so you can hit the ground running with an API that is familiar.