The great trajedy of Unix -- and of of the greater trajedies of computation -- is that the composable, user-visible components that made Unix great have never been matched in later stuff, not even in Unix stuff.

We have lots of systems which make software modular and composable, but they are not for the end user. At best they end up being build-blocks for programmers who make gigantic black boxes. More often, programmers of gigantic black boxes struggle with tools and libraries that are themselves gigantic black boxes.