Are there any equivalent of Qt style loosely coupled "Signals and Slots" based JavaScript UI library? Qt allows widget/ components to be connected to each other with a pub-sub type of system where the emitter of the signal really need not care who the consumer is. While, IIUC, most JS libraries follow a hierarchically coupled state passing system where sharing of state happens through props/ passing down from parent to child components with lifted state etc., Was wondering if there are any JS libraries which operate in the style of Qt event driven signal-slot connections as a primary paradigm.