Cassandra 3.11.0 is about to be included in Fedora. There are some tweaks to the sources we need to do in order to successfully build it. Cassandra depends on slf4j 1.7.7, but In Fedora we have the latest upstream version 1.7.21 It was released some time ago on April 6 2016. I attached a patch updating Cassandra sources to depend on the newer slf4j sources. The only actual change is the number of parameters accepted by SubstituteLogger class. Please consider updating.