# any-of ( mysql postgres sqlite )
sys-cluster/cinder postgres
sys-cluster/csync2 postgres
sys-cluster/neutron postgres
sys-cluster/nova postgres

# any-of (chrome qt4)
net-misc/hotot qt4

# any-of ( chrome qt5 )
net-misc/hotot qt5

# any-of ( mysql postgres sqlite )
mail-client/roundcube sqlite

# any-of ( iptables nftables )
net-misc/connman iptables

# any-of ( emacs fcitx4 ibus )
app-i18n/mozc -ibus fcitx4

# any-of ( cgi mono perl go lua php pypy python python_asyncio python_gevent ruby )
www-servers/uwsgi python

# any-of ( proxy account container object )
sys-cluster/swift container

# any-of ( java lua mono perl php python ruby tcl )
dev-libs/xapian-bindings python

# at-most-one-of ( alsa pulseaudio )
games-action/descent3-demo alsa -pulseaudio

# any-of ( mysql postgres sqlite )
mail-client/roundcube postgres -sqlite