Database systems have been able to deal with concurrent updates for quite some time now, so I don't think doing this is technically difficult with the current state of the art. Individual dev teams might not be well versed in the current state of the art, but the correct business response to that is not to restrict your business rules but to get developers who are well versed in the current state of the art.
> Database systems have been able to deal with concurrent updates for quite some time now, so I don't think doing this is technically difficult with the current state of the art.
Traditional ACID systems can't really handle them nicely - your only choice with an update is to commit it or discard it - so you have to do a lot of handwritten logic on top, and even if the database itself handles that well, the layers above it generally don't. Event-sourcing style systems work well but they're still not really mainstream yet.
