I wrote a post about a problem Homebrew sees pretty often on OS X where projects link extension modules with -lpython (either explicitly or because they trust python-config --ldflags). If you see somebody doing this, please point them to this post and invite them to use -undefined dynamic_lookup instead, so that the Python symbols are resolved at import time. http://blog.tim-smith.us/2015/09/python-extension-modules-os-x/ Cheers, Tim