Max external template with CMake
I put together a starter template for building Max externals with CMake.
It's a plain object box that adds two numbers. The object itself doesn't matter; it's there so the package is complete and buildable rather than a fragment. What you get is a CMake build that produces a universal binary and ad-hoc signs it, max-sdk-base wired up as a submodule so a --recursive clone builds immediately, the full package layout including a help patch and a reference page, and comments through the source explaining the non-obvious SDK calls.
The logic sits in a separate file that contains no Max code, with the object file handling only the Max side. Replacing that one file is most of what making your own object involves.
BUILD.md is probably the more useful part. It documents seven SDK behaviors that produce misleading symptoms rather than errors — three of them surface as no such object from completely unrelated causes, and one produces an Intel-only binary while still reporting a successful build. Each entry gives the symptom alongside the cause, since the symptom is what you'll have in front of you.
Verified on macOS, Apple Silicon. Windows is untested — nothing in it is deliberately mac-only, but I haven't built it there. :-)
MIT licensed. Corrections welcome.