1. Yeah, hence "Well, I guess to some degree this is a result of payment processors being incompetent [...]". 2. That is actually not a solution. As your commu

1. Yeah, hence "Well, I guess to some degree this is a result of payment processors being incompetent [...]". 2. That is actually not a solution. As your communication channel is asynchronous and unordered, there are no ordering guarantees on the delivery of the transaction request and any subsequently sent status queries, thus this approach has a race condition. Also, chances are that such broken systems don't even give you any useful visibility guarantees on "received" transactions, so even if you pretend that IP is synchronous if you wait long enough chances are you'll still have race conditions.