C++ build systems and compilation time in general is basically my most significant complaint as a C++ developer.

There are so many disparate build systems, none of them are intuitive, none of them do much in the way of error checking or give good user feedback, and the resulting build is always slow.

And as for the code itself, there's no type of linter or checker that will tell you if there's a way to save on compile time. "Hey, this could be a forward decl instead of a include!", or "Hey, this include is completely unused!" or some such. (There's include-what-you-use but I could not for the life of me figure out how to make it work)

I know the problems are hard, I just wish more effort was expended to make the whole process less painful and slow.