/usr/include/ircd-hybrid-8/ is in hybrid-dev 1:8.2.12+dfsg.1-1.
This file is owned by root:root, with mode 0o755.
..
/usr/include/ircd-hybrid-8/auth.h
/usr/include/ircd-hybrid-8/channel.h
/usr/include/ircd-hybrid-8/channel_mode.h
/usr/include/ircd-hybrid-8/client.h
/usr/include/ircd-hybrid-8/conf.h
/usr/include/ircd-hybrid-8/conf_class.h
/usr/include/ircd-hybrid-8/conf_db.h
/usr/include/ircd-hybrid-8/conf_pseudo.h
/usr/include/ircd-hybrid-8/dbuf.h
/usr/include/ircd-hybrid-8/defaults.h
/usr/include/ircd-hybrid-8/event.h
/usr/include/ircd-hybrid-8/fdlist.h
/usr/include/ircd-hybrid-8/hash.h
/usr/include/ircd-hybrid-8/hostmask.h
/usr/include/ircd-hybrid-8/id.h
/usr/include/ircd-hybrid-8/ipcache.h
/usr/include/ircd-hybrid-8/irc_string.h
/usr/include/ircd-hybrid-8/ircd.h
/usr/include/ircd-hybrid-8/ircd_defs.h
/usr/include/ircd-hybrid-8/ircd_getopt.h
/usr/include/ircd-hybrid-8/ircd_signal.h
/usr/include/ircd-hybrid-8/isupport.h
/usr/include/ircd-hybrid-8/list.h
/usr/include/ircd-hybrid-8/listener.h
/usr/include/ircd-hybrid-8/log.h
/usr/include/ircd-hybrid-8/memory.h
/usr/include/ircd-hybrid-8/mempool.h
/usr/include/ircd-hybrid-8/misc.h
/usr/include/ircd-hybrid-8/modules.h
/usr/include/ircd-hybrid-8/motd.h
/usr/include/ircd-hybrid-8/numeric.h
/usr/include/ircd-hybrid-8/packet.h
/usr/include/ircd-hybrid-8/parse.h
/usr/include/ircd-hybrid-8/patchlevel-debian.h
/usr/include/ircd-hybrid-8/patchlevel.h
/usr/include/ircd-hybrid-8/res.h
/usr/include/ircd-hybrid-8/reslib.h
/usr/include/ircd-hybrid-8/restart.h
/usr/include/ircd-hybrid-8/resv.h
/usr/include/ircd-hybrid-8/rng_mt.h
/usr/include/ircd-hybrid-8/rsa.h
/usr/include/ircd-hybrid-8/s_bsd.h
/usr/include/ircd-hybrid-8/send.h
/usr/include/ircd-hybrid-8/serno.h
/usr/include/ircd-hybrid-8/server.h
/usr/include/ircd-hybrid-8/stdinc.h
/usr/include/ircd-hybrid-8/user.h
/usr/include/ircd-hybrid-8/userhost.h
/usr/include/ircd-hybrid-8/watch.h
/usr/include/ircd-hybrid-8/whowas.h