case erlang:function_exported(rebar3, main, 1) of
    true -> % rebar3
        CONFIG;
    false -> % rebar 2.x or older
        NewDeps = {deps, [{jsonx, "", {git, "https://github.com/alertlogic/jsonx.git", {branch, master}}}]},
        lists:keyreplace(deps, 1, CONFIG, NewDeps)
end.