anchor.diff:  { stdenv
   , fetchurl
  +, lib
   , writeText
   
   , freetype
   , fontconfig
  +, libx11
  +, libxext
  +, libxft
  +, libxrender
   , ncurses
  -, xorg
  +, xorgproto
   
   , config ? null
   , configFile ? null
  
positive.code: in
  stdenv.mkDerivation rec {
    name = "st-0.7";
    
    src = fetchurl {
      url = "http://dl.suckless.org/st/${name}.tar.gz";
      multihash = "QmV1FssAdXN44hWi4QjWp5GLn5ZqwqnvBjJ8JRNayMRi5Z";
  
negative.code: assert config != null -> configFile == null;
  
  let
    inherit (lib)
      optionalString;
  
    configFile' =
  