What is the RxJS equivalent of the Bacon.js bus?

The RxJS equivalent is called Subject. This is both the Observer and the Observed. Therefore, in order to push events to it, you use the Observer interface: the onNext, onError, and onCompleted methods. Then you can subscribe to it, match the map, zip code, filter it like any Observable. Here's an example from the official docs:

var subject = new Rx.Subject();

var subscription = subject.subscribe(
    function (x) { console.log('onNext: ' + x); },
    function (e) { console.log('onError: ' + e.message); },
    function () { console.log('onCompleted'); });

subject.onNext(1);
// => onNext: 1

subject.onNext(2);
// => onNext: 2

subject.onCompleted();
// => onCompleted

subscription.dispose();

      

        
        
        
      

    

You can check out the theme getting started guide here and the Subject API docs.