anchor.diff:      type WidgetEvents =
       | Created of WidgetCreatedEvent
   
  +    type WidgetCounterEvents =
  +    | Counted of WidgetCreatedEvent
  +
       let stateBuilder = StateBuilder.Empty ()
   
       let widgetHandlers = 
  
positive.code: module AggregateIntegrationTests = 
      type AggregateType =
      | Widget
  
      type WidgetId = 
          {
  
negative.code:                yield addWidget
                       |> simpleHandler stateBuilder
                       |> buildCmd
              }
  
      let widgetCounterAggregate =
          aggregate<unit,WidgetCounterEvents,WidgetId,AggregateType>
              AggregateType.WidgetCounter stateBuilder
              {
                  let getId (evt : WidgetCreatedEvent) = evt.WidgetId
                  yield linkEvent getId WidgetCounterEvents.Counted
              }
  
      let handlers =
  