As the owner of a mac with an amd gpu, I'm very excited to see support coming soon. Been wanting to get into ml but been pretty discouraged with all of the popular libraries being cuda-only.
You would need to: bazel build -c opt plaidml:wheel plaidml/keras:wheel
and then
sudo pip install bazel-bin/plaidml/whl bazel-bin/plaidml/keras/whl