[Nix-dev] nested child configurations - was: multiple full systemprofiles

[Michael Raskin]

>What I would like:
>- Give child-profiles some link back to their parent. If a real link
>would give cyclic dependency issues, a text file with just the store
>path is probably enough too.

Unfortunately, this still means circular dependency. Store paths 
mentioned inside store elements always mean dependencies, and if you can
go from a pth to itself via such mentions, you have found a dependency 
loop.

What you should consider is using /nix/var/nix/profiles/system-*-link

If I remember correctly, it is not affected by switches.

While you are at that, I was always too lazy to add all children of 
top-3 (top n with n being parameter?) configurations in GRUB menu. If
your use case would be helped by this idea, actually changing the script
should be easy.


>I can then just use helper scripts to list all available child-configs
>(from the top-level configuration) and switch to them.
>- Have "nixos-rebuild boot" print the path to the config it just built
>Then I can switch to the new config's child variant myself, performing
>a child-to-child jump.

That can be done via 

nixos-rebuild pull && nix-build /etc/nixos/nixos -A system --no-out-link