You have to love systems people who tell software people how the software works. Especially when you are trying to tell them why a problem is occurring in the software. Like software guy is like:

"this is breaking because a number is getting overwritten in the system by a product we interface with and have no control over"

"Well you need to stop the number from getting overwritten"

"then we're going to have to overhaul the design of the system"

"you don't have to redesign the system, you just need to circumvent the product that is overwriting the number"

"Yeah, a design change."

Dude is the interim system lead and starting to get uppity. Even though it's his group that is behind which is why we are driving changes to the system rather than them.