anchor.diff:      ${optionalString withPerl534    "./configure perl   --module=perl534  --perl=${perl534}/bin/perl"}
       ${optionalString withPerldevel  "./configure perl   --module=perldev  --perl=${perldevel}/bin/perl"}
       ${optionalString withRuby_2_7   "./configure ruby   --module=ruby27   --ruby=${ruby_2_7}/bin/ruby"}
  +    ${optionalString withRuby_3_0   "./configure ruby   --module=ruby30   --ruby=${ruby_3_0}/bin/ruby"}
     '';
   
     postInstall = ''
  
positive.code: , withPerl532 ? false, perl532
  , withPerl534 ? true, perl534
  , withPerldevel ? false, perldevel
  , withRuby_2_7 ? false, ruby_2_7
  , withSSL ? true, openssl ? null
  , withIPv6 ? true
  , withDebug ? false
  
negative.code:     ++ optional withPerl534 perl534
      ++ optional withPerldevel perldevel
      ++ optional withRuby_2_7 ruby_2_7
      ++ optional withRuby_3_0 ruby_3_0
      ++ optional withSSL openssl;
  
    configureFlags = [
  