ZNC is developed by these people:

Prozac <prozac@rottenboy.com>
Jim Hull <code@jimloco.com>
Uli Schlachter <psychon@znc.in>
SilverLeo
kroimon <znc@kroimon.de>
flakes
Alexey "DarthGandalf" Sokolov
Kyle Fuller <inbox@kylefuller.co.uk>

These people, in no particular order, have helped develop ZNC, for example by
sending in patches, writing new modules or finding significant bugs:

Kuja <Kuja@znc.in> - runs and pays for znc.in
derblubber
toby <ich@toby.in>
Zack3000
d4n13L <daniel@danielschmitz.de> - graphiX webadmin skin
Veit "Cru" Wahlich <cru@ircnet.de>
crox
Freman (http://fremnet.net/contact)
Sebastian Ramacher <sebastinas@users.sourceforge.net>
cnu - master of destruction (security issues)
Ingmar "KiNgMaR" Runge <mail@irsoft.de>
Michael "Svedrin" Ziegler <diese-addy@funzt-halt.net>
Robert Lacroix (http://www.robertlacroix.com)
Martin "Nirjen" Martimeo <martin@martimeo.de>
Reed Loden <reed@reedloden.com>
Brian Campbell (bcampbell@splafinga.com)
Joshua M. Clulow (http://sysmgr.org)
evaryont <colin@evaryont.me>
Michael "adgar" Edgar <adgar@carboni.ca>
Jens-Andre "vain" Koch <jakoch@web.de>
Heiko Hund <heiko@ist.eigentlich.net> - cyrusauth module

If you did something useful and want to be listed here too, add yourself and submit the patch.