Programming model popularized by React+MobX and Ember: the application maintains observable state, dispatches actions that update it, and derives the virtual DOM (and thus the UI) from that state. Developers no longer think about when and how to update individual components because the framework re-derives the view from state. Panel argument: the best code is no code — reusing framework conventions means less custom, less to test, and easier recovery when APIs change. Contrasted with Redux-like approaches where developers write more code to thread data through the app.