Connecting to Rx Observable in Node.js with Rx Observer in .NET within one process using Edge.js.

RxEdge

var edge = require('edge'); // http://tjanczuk.github.io/edge
var Rx = require('rx'); // https://github.com/Reactive-Extensions/RxJS

var createSubject = edge.func({
  source: function () {/*
    using System.Reactive.Linq;
    using System.Reactive.Subjects;

    async (dynamic input) => {
      var s = new Subject<object>();

      return new {
        subscribe = (Func<object,Task<object>>)(async (observer) => {
          s.Subscribe(x => {
                        ((Func<object,Task<object>>)observer)(x);
          });
          return null;                                                                  
        }),                                                      
        onNext = (Func<object,Task<object>>)(async (data) => {
          s.OnNext((object)data);
          return null;
        })                                                       
      };
    }
  */},
  references: [
                 __dirname + '\\System.Reactive.Core.dll',
                 __dirname + '\\System.Reactive.Linq.dll',
                 __dirname + '\\System.Reactive.Interfaces.dll',
                 'System.Runtime.dll',
                 'System.Threading.Tasks.dll'
  ]
});

var MySubject = (function () {
  return function () {
    var subject = createSubject(null, true);

    var observer = Rx.Observer.create(function (x) {
      subject.onNext(x, true);
    });

    var observable = Rx.Observable.create(function (obs) {
      subject.subscribe(function (data, cb) {
        process.nextTick(function () {
          obs.onNext(data);
        });
        cb();
      });
    });

    return Rx.Subject.create(observer, observable);
  }
}());

var s = new MySubject();

s.subscribe(function (data) {
  console.log('Got data: ' + data);
});

Rx.Observable.timer(0, 500)
  .take(10)
  .subscribe(function (x) {
    s.onNext(x);
  });