anchor.diff:  { stdenv, fetchurl, groff }:
   
  -with stdenv.lib;
  -stdenv.mkDerivation rec {
  -
  +let version = "51"; in
  +stdenv.mkDerivation {
     name = "mksh-${version}";
  -  version = "R50d";
   
     src = fetchurl {
       urls = [
  -      "http://www.mirbsd.org/MirOS/dist/mir/mksh/${name}.tgz"
  -      "http://pub.allbsd.org/MirOS/dist/mir/mksh/${name}.tgz"
  +      "http://www.mirbsd.org/MirOS/dist/mir/mksh/mksh-R${version}.tgz"
  +      "http://pub.allbsd.org/MirOS/dist/mir/mksh/mksh-R${version}.tgz"
       ];
  -    sha256 = "10prcdffwziksq9sw96c1r09h4kg2zwznybrggzmjfa6l4k8h9m2";
  +    sha256 = "1pyscl3w4aw067a5hb8mczy3z545jz1dwx9n2b09k09xydgsmvlz";
     };
   
     buildInputs = [ groff ];
  
positive.code:     install -D -m 644 dot.mkshrc $out/share/mksh/mkshrc
    '';
  
    meta = {
      description = "MirBSD Korn Shell";
      longDescription = ''
        The MirBSD Korn Shell is a DFSG-free and OSD-compliant (and OSI
  
negative.code:       systems.
      '';
      homepage = "https://www.mirbsd.org/mksh.htm";
      license = licenses.free;
      maintainers = [ maintainers.AndersonTorres ];
      platforms = platforms.unix;
    };
  