Correct way to access M1 dylibs in the delocate command?

[MrBitBucket]

I figured out most of the problems wrt making M1 extensions. I did the following

1. made setup.py check for the arm64 build and download some files which my boss built on his M1 machine;
   the downloaded were extracted under build/m1stuff/m1stuff/opt/homebrew/{lib,include}

2. setup.py then adjusted the include and library paths to use those files. The load command appeared to work OK
   and didn't complain about incompatible libs etc.

3. I used this command to try and delocate

CIBW_REPAIR_WHEEL_COMMAND_MACOS: >
  if [ "{delocate_archs}" = "arm64" ]; then
    DYLD_LIBRARY_PATH={project}/build/m1stuff/m1stuff/opt/homebrew/lib delocate-listdeps {wheel} &&
    DYLD_LIBRARY_PATH={project}/build/m1stuff/m1stuff/opt/homebrew/lib delocate-wheel --require-archs {delocate_archs} -w {dest_dir} {wheel}
  else
    delocate-listdeps {wheel} &&
    delocate-wheel --require-archs {delocate_archs} -w {dest_dir} {wheel}
  fi

but I get a complaint about a missing key (I think {project}) from cibuildwheel code. Is there a simple way to get back to my dylibs under build/ or should I try to install resources somewhere else?

[MrBitBucket]

To answer my own question it seems much easier to load the resources under /tmp/reportlab-cache and then refer directly to them there.

At long last I can get the arm64 wheel built and it does contain the needed dylibs.

I need to get my boss to try it out though as he's the one with the m1 machine.