anchor.diff:    # Perl is required for it's pod2man.
     # Python and Perl are required for patching the script interpreter paths.
     nativeBuildInputs = [ autoconf automake makeWrapper ];
  -  buildInputs = [ python perl perlPackages.GnuPGInterface libmd gnupg1 ];
  +  buildInputs = [ python3 perl perlPackages.GnuPGInterface libmd gnupg1 ];
   
     postInstall = ''
       # Install all tools which aren't handled by 'make install'.
  
positive.code: { stdenv, fetchurl, autoconf, automake, makeWrapper
  , python, perl, perlPackages
  , libmd, gnupg1, which, getopt, libpaper, nettools, qprint
  , sendmailPath ? "/run/wrappers/bin/sendmail" }:
  
  let
    # All runtime dependencies from the CPAN graph:
    # https://widgets.stratopan.com/wheel?q=GnuPG-Interface-0.52&runtime=1&fs=1
    # TODO: XSLoader seems optional
    GnuPGInterfaceRuntimeDependencies = with perlPackages; [
      strictures ClassMethodModifiers DataPerl DevelGlobalDestruction ExporterTiny
      GnuPGInterface ListMoreUtils ModuleRuntime Moo MooXHandlesVia MooXlate
  
negative.code:   '';
  
    meta = with stdenv.lib; {
      homepage = https://salsa.debian.org/debian/signing-party;
      description = "A collection of several projects relating to OpenPGP";
      longDescription = ''
        This is a collection of several projects relating to OpenPGP.
  