anchor.diff:  
       in
         # Declare the ISO as a build product so that it shows up in Hydra.
  -      runCommand "nixos-iso-${version}"
  +      runCommand "nixos-iso-${config.system.nixosVersion}"
           { meta = {
               description = "NixOS installation CD (${description}) - ISO image for ${system}";
               maintainers = map (x: lib.getAttr x lib.maintainers) maintainers;
  
positive.code: 
      with import <nixpkgs> {inherit system;};
      let
        version = builtins.readFile ./.version + (lib.optionalString (!officialRelease) versionSuffix);
  
        versionModule = { system.nixosVersion = version; };
  
        config = (import lib/eval-config.nix {
          inherit system;
  
negative.code:       releaseTools.makeSourceTarball {
          name = "nixos-tarball";
  
          src = nixosSrc;
  
          inherit officialRelease version;
  
          distPhase = ''
            echo -n $VERSION_SUFFIX > .version-suffix
  