Licensing (GPL incompatible with EPL)
It seems as if GeoPub can not be distributed under GPLv3 as GPL is incompatible with the license of most Clojure libraries (EPL) (see the GNU FAQ and the EPL FAQ).
The solution seems to be include an exception allowing linking to EPL libraries (https://www.gnu.org/licenses/gpl-faq.html#GPLIncompatibleLibs). See for example how this was done for the metabase project: https://github.com/metabase/metabase/commit/666b1b453a71a1fca19e7b81739a58ce7fa45a14