I would strongly disagree that React is immediate mode UI. Sure, it's UI implemented as a function. But each of those functions relates to a single visual component, and each is (almost always) declaratively described using JSX. The render function is stateless, but the components are not - you put your state in the 'props', and display it using a pretty standard data binding method, and respond to user input via the usual event-driven model, often hooked to a method that exists inside the component.