Interface Segregation Principle

If a source file changes, you have to recompile everybody who depends on that source file. This was really important in C++ where a pound include was involved. It's also important in Java and C sharp, although not quite as important. Some people play a funny game where they change the signature of a method. And then the other files that don't care about it just don't bother to recompile them. We've found everybody who did that in the system and I'm back.