It also highlights the importance of writing isolatable code. The simplest way to do that is to write code that doesn’t use any global variables, but this is s

It also highlights the importance of writing isolatable code. The simplest way to do that is to write code that doesn’t use any global variables, but this is something that even experienced developers can’t seem to wrap their heads around in my observation. Even languages like Java that don’t allow global variables end up having them simulated with dozens of “singletons” that are referenced everywhere that do things that make targeted troubleshooting impossible.