MassTransitDispatcher.cs

 internal class MassTransitDispatcher : IObserver<ICommit>
    {
        private readonly IServiceBus _bus;

        public MassTransitDispatcher(IServiceBus bus)
        {
            _bus = bus;
        }

        public void Dispose()
        {
            
        }

        public void OnNext(ICommit commit)
        {
            foreach (var @event in commit.Events)
            {
                _bus.Publish(@event);
            }
        }

        public void OnError(Exception error)
        {
            // ...
        }

        public void OnCompleted()
        {
        }
    }

PollingHook.cs

  internal class PollingHook : PipelineHookBase
    {
        private readonly IObserveCommits _commitsObserver;

        public PollingHook(IObserveCommits commitsObserver)
        {
            _commitsObserver = commitsObserver;
        }

        public override void PostCommit(ICommit committed)
        {
            base.PostCommit(committed);
            _commitsObserver.PollNow();
        }
    }

stuff.cs

var massTransitDispatcher = new MassTransitDispatcher(_bus);
var eventStore = Wireup.Init()
    // .......
    .Build();

var repository = new EventStoreRepository(eventStore, new AggregateFactory(), new ConflictDetector());
var pollingClient = new PollingClient(eventStore.Advanced);
var commitObserver = pollingClient.ObserveFrom(null);
var subscription = commitObserver.SubscribeSafe(massTransitDispatcher);