anchor.diff:  
     imports = [
       (mkAliasOptionModule [ "services" "compton" ] [ "services" "picom" ])
  +    (mkRemovedOptionModule [ "services" "picom" "refreshRate" ] ''
  +      This option corresponds to `refresh-rate`, which has been unused
  +      since picom v6 and was subsequently removed by upstream.
  +      See https://github.com/yshui/picom/commit/bcbc410
  +    '')
     ];
   
     options.services.picom = {
  
positive.code:       # other options
        backend          = cfg.backend;
        vsync            = cfg.vSync;
        refresh-rate     = cfg.refreshRate;
      };
  
      systemd.user.services.picom = {
  
negative.code:       '';
      };
  
      settings = with types;
      let
        scalar = oneOf [ bool int float str ]
  