anchor.diff:  
     config = {
   
  -    nix.chrootDirs = [ "/bin" ];
  -
       environment.etc."nix/nix.conf".source = nixConf;
   
       # List of machines for distributed Nix builds in the format
  
positive.code:         build-users-group = nixbld
          build-max-jobs = ${toString (cfg.maxJobs)}
          build-use-chroot = ${if cfg.useChroot then "true" else "false"}
          build-chroot-dirs = ${toString cfg.chrootDirs} $(echo $extraPaths)
          binary-caches = ${toString cfg.binaryCaches}
          trusted-binary-caches = ${toString cfg.trustedBinaryCaches}
          $extraOptions
  
negative.code: 
    nixConf =
      let
        # If we're using a chroot for builds, then provide /bin/sh in
        # the chroot as a bind-mount to bash. This means we also need to
        # include the entire closure of bash.
        sh = pkgs.stdenv.shell;
        binshDeps = pkgs.writeReferencesToFile sh;
      in
        pkgs.runCommand "nix.conf" {extraOptions = cfg.extraOptions; } ''
          extraPaths=$(for i in $(cat ${binshDeps}); do if test -d $i; then echo $i; fi; done)
  