A separate invalidation stream sounds like a really bad idea and is asking for race conditions. Just put the invalidation events on the same stream with the inf

A separate invalidation stream sounds like a really bad idea and is asking for race conditions. Just put the invalidation events on the same stream with the information necessary to revert the original transaction (such as the balance to restore in addition to stating the original transaction is invalidated); it's okay to denormalize on the same stream in these situations.