Modern? Initially written in 1997 in god old perl. Most of the source hasn't been touched in years and still uses old perl style constructs instead of "modern" perl. Perl "Objects" are handly stitched together with "bless" instead of modern perl modules like Moose, Moo or sth. else. So no Sympa is by far not a modern software in case of mailman. And I do not want have a boiling piece of junk lying aroung in my plesk servers doing webfrontend and mails - and I am doing perl for 20+ years.