oh sorry, to be clear, the real error is the recurring:

Exception message: dlopen(/Users/dmcclanahan/tools/p1/native_engine.so, 2): Symbol not found: _wrapped_PyInit_native_engine
  Referenced from: /Users/dmcclanahan/tools/p1/native_engine.so
  Expected in: flat namespace
 in /Users/dmcclanahan/tools/p1/native_engine.so

i removed

-undefined dynamic_lookup

from

engine_cffi/build.rs

to try to get it to fail at build time instead of runtime, and produced the above message, which was progress