If the derivation has already been written (as GP implies), then compiling something yourself with Nix is essentially just a longer installation process. No dow

If the derivation has already been written (as GP implies), then compiling something yourself with Nix is essentially just a longer installation process. No downloading tarballs, no keeping track of things in /usr/local, no stow or manually adding things to your path. Nix is essentially a source distribution that pulls common binaries from caches.