Would you mind elaborating? Who would you say are the competitors? I completely agree it's a waste to over complicate things if you never leverage it, but Nix seems like the perfect solution to a problem I can't imagine I'm the only one to have. Being able to build against different versions of glibc and a whole stack of dependencies out of the box is kind of amazing after dealing with dependencies. Flipping between version stacks by flipping a symlink is insane.