As soon as you clone, follow these steps:
mkdir elib
cd elib
git clone https://github.com/jchris/erlang-json-eep-parser.git
cd erlang-json-eep-parser
erlc json_eep.erl
erlc json_grammar.erl
erlc json_lex2.erl
mv *beam ..
cd ../..
# rm -rf erlang-json-eep-parser
make full_testshunit tests are not implemented yet.
More info at http://seguridad-agile.blogspot.com/2013/07/mutation-testing-framework.html