Nix can already encompass stack/cabal, cargo, pip, gem, and npm in a single system. I never need to use 'npm install', 'cabal install' or virtualenv/pip anymore

Nix can already encompass stack/cabal, cargo, pip, gem, and npm in a single system. I never need to use 'npm install', 'cabal install' or virtualenv/pip anymore. Nix does it all for me. So if your concern is that you have too many package management systems already, take another look at Nix, as it can probably replace them all. (Except for the App Store... no way to manage App Store apps with Nix.)