anchor.diff:  
       nix.envVars =
         { NIX_CONF_DIR = "/etc/nix";
  -
  +      }
  +
  +      // optionalAttrs (!isNix112) {
           # Enable the copy-from-other-stores substituter, which allows
           # builds to be sped up by copying build results from remote
           # Nix stores.  To do this, mount the remote file system on a
  
positive.code:   cfg = config.nix;
  
    nix = cfg.package.out;
  
    makeNixBuildUser = nr:
      { name = "nixbld${toString nr}";
  
negative.code: 
        // optionalAttrs cfg.distributedBuilds {
          NIX_BUILD_HOOK =
            if isNix112 then
              "${nix}/libexec/nix/build-remote"
            else
              "${nix}/libexec/nix/build-remote.pl";
        };
  
      # Set up the environment variables for running Nix.
  