Each macOS leg runs on a Mac of its own architecture. The x86_64 one was cross-built on the
Apple-silicon runner, where the step that runs the archive's own wai (hello, verify,
dev --check) and the wheel's smoke test on Python 3.9 are skipped, since they run only when
the triple is the host's: the x86_64 archive and wheel were attached without ever being run.
On the Intel Mac (the iMac Pro, label macos-x86_64) both run natively. The two legs are on
different hosts now, so max-parallel: 1 is gone.
Co-Authored-By: Claude Opus 5.5 <[email protected]>