The only way to get reproducible environments is to have an immutable base OS with packages compiled without environment, library, or fs leaks. In the real worl

The only way to get reproducible environments is to have an immutable base OS with packages compiled without environment, library, or fs leaks. In the real world, this requires lots of patching and isolation (hypervisor and/or containers). Unfortunately, Nix suffers the fate of Haskell: so powerful that the masses can't and don't use it. By contrast, Homebrew spreads like cancer. "Worse is better".