anchor.diff:  
       meta = with lib; {
         description = "A tool to read, write and edit EXIF meta information";
  +      longDescription = ''
  +        ExifTool is a platform-independent Perl library plus a command-line
  +        application for reading, writing and editing meta information in a wide
  +        variety of files. ExifTool supports many different metadata formats
  +        including EXIF, GPS, IPTC, XMP, JFIF, GeoTIFF, ICC Profile, Photoshop
  +        IRB, FlashPix, AFCP and ID3, as well as the maker notes of many digital
  +        cameras by Canon, Casio, DJI, FLIR, FujiFilm, GE, GoPro, HP,
  +        JVC/Victor, Kodak, Leaf, Minolta/Konica-Minolta, Motorola, Nikon,
  +        Nintendo, Olympus/Epson, Panasonic/Leica, Pentax/Asahi, Phase One,
  +        Reconyx, Ricoh, Samsung, Sanyo, Sigma/Foveon and Sony.
  +      '';
         homepage = "https://exiftool.org/";
   
         license = with licenses; [ gpl1Plus /* or */ artistic2 ];
  
positive.code: 
      meta = {
        description = "AutoDia, create UML diagrams from source code";
        homepage = "http://www.aarontrevena.co.uk/opensource/autodia/";
        license = with lib.licenses; [ gpl2Plus ];
        mainProgram = "autodia.pl";
  
negative.code:     };
    };
  
    MailMaildir = buildPerlPackage {
      version = "1.0.0";
      pname = "Mail-Maildir";
      src = fetchurl {
        url = "mirror://cpan/authors/id/Z/ZE/ZEROALTI/Mail-Maildir-100/Mail-Maildir-1.0.0.tar.bz2";
        sha256 = "1krkqfps6q3ifrhi9450l5gm9199qyfcm6vidllr0dv65kdaqpj4";
      };
    };
  
    MailBox = buildPerlPackage {
      version = "3.009";
      pname = "Mail-Box";
  