anchor.diff:      system.build.etc = pkgs.runCommand "etc" {} ''
         mkdir -p $out/etc
         cd $out/etc
  +      ${concatMapStringsSep "\n" (attr: "mkdir -p $(dirname '${attr.target}')") etc}
         ${concatMapStringsSep "\n" (attr: "ln -s '${attr.source}' '${attr.target}'") etc}
       '';
   
  
positive.code:       for link in $(ls /etc/static/); do
          if [ -e "/etc/$link" ]; then
            if [ ! -L "/etc/$link" ]; then
              echo "warning: /etc/$link is a file, skipping..." >&2
            fi
          else
            ln -sfn "/etc/static/$link" "/etc/$link"
  
negative.code:     mkTextDerivation = name: text: pkgs.writeText "etc-${name}" text;
    };
  
    hasDir = path: length (splitString "/" path) > 1;
  
    etc = filter (f: f.enable) (attrValues config.environment.etc);
    etcDirs = filter (attr: hasDir attr.target) (attrValues config.environment.etc);
  
  in
  
  