MarsSeed [1] filed a deletion request for cassandra30 [2]: EOL, unmaintained legacy Cassandra version 3.0 (not v30 as pkgname suggests). Not needed or useful to keep anymore.
AUR has a newer cassandra package. [1] https://aur.archlinux.org/account/MarsSeed/ [2] https://aur.archlinux.org/pkgbase/cassandra30/
