React JS is part of Facebook’s “Flux” architecture, which was created for many of the same reasons Sonar was created. As you can see by comparing the two diagrams on this page, Sonar makes “server push” an optional flow. This is because many of the applications we build don’t need server push. However, we recently worked on a home automation application that used Firebase as the server push data source. React is designed especially for the “realtime server push” or “callback” pattern.