It depends how you do it. Everything is a tradeoff. Do you want everything to get assembled on your laptop and pushed to your machines? That means your laptop ends up holding a copy of every package that's going to any machine. Do you want each machine to do its own config build, merely being "puppeted" by your laptop? That could be slow if your machines are small embedded devices. Or maybe you want to run the builds on a beefy remote server because you are doing custom builds from source instead of using the cache... All of this is possible with Nix, but there are real design considerations.