Exception message: dlopen(/var/folders/4t/btjfp2sn7pldd1h5_fn6mwxc0000gn/T/tmpxlub89n1/native_engine.so, 2): Symbol not found: _tasks_singleton_add
  Referenced from: /var/folders/4t/btjfp2sn7pldd1h5_fn6mwxc0000gn/T/tmpxlub89n1/native_engine.so
  Expected in: flat namespace
 in /var/folders/4t/btjfp2sn7pldd1h5_fn6mwxc0000gn/T/tmpxlub89n1/native_engine.so