I would think the bootstrap for cross-compile would be pretty close to the answer to your question. Guix has pretty radical goals in comparison to Nix, which i

I would think the bootstrap for cross-compile would be pretty close to the answer to your question. Guix has pretty radical goals in comparison to Nix, which is itself relatively radical. Bootstrapping Nix is... maybe less useful to optimize? I'm not saying it's not worth solving, but as an end user I really don't care if my packages are built from source or not, as long as I can, for example, use Spotify.