Its outrageous that no one pointed out git. Its the perfect example of this. I consider code version control a solved problem post git.

GP here. I agree, git is the best example in the spirit of my comment.

Maybe the reason it wasn’t pointed out is precisely because it’s so obviously good that it’s no longer a conscious choice, and then we forget life before it. Even those of us who experienced it.

What about source files that aren't lines of text?