protected override void OnRecover(object message)
        {
            switch (message)
            {
            case Evt evt:
                UpdateState(evt);
                break;

            case SnapshotOffer snapshot when snapshot.Snapshot is ExampleState:
                _state = (ExampleState)snapshot.Snapshot;
                break;
            }
        }
 private void UpdateState(Evt evt)
 {
     _state = _state.Updated(evt);
 }