The ArcGIS Maps SDK for JavaScript's widgets have a clean separation between the user interface (the "view") and the underlying business logic ("viewModel"), allowing developers to use the viewModel to create a custom experience. In this session, you will learn how you can create custom UIs using the widget viewModels. We will look at examples using viewModels to create UIs within popular web frameworks and libraries, as well as the Calcite Design System using web components.