anchor.diff:  
       home.activation.linkGeneration = dagEntryAfter ["writeBoundary"] (
         let
  -        pattern = "-home-manager-files/";
  -
           link = pkgs.writeText "link" ''
             newGenFiles="$1"
             shift
  
positive.code:       safeName = replaceStrings unsafeInName (empties unsafeInName) path;
      in
        "home_file_" + safeName;
  
  in
  
  
negative.code:             relativePath="''${sourcePath#$newGenFiles/}"
              targetPath="$HOME/$relativePath"
              if [[ -e "$targetPath" \
                  && ! "$(readlink "$targetPath")" == ${homeFilePattern} ]] ; then
                errorEcho "Existing file '$targetPath' is in the way"
                collision=1
              fi
  