[reaperhulk]

Many of the problems people appear to be having with pyenv on M1 are related to it pulling include paths for homebrew that include homebrew libffi, but not passing the library path. For cases like cffi this results in header/library mismatch and you get runtime dynamic linker errors.

Other replies here appear to assume basic compilation issues, but the issues I've seen on various GitHub projects are mostly related to these more insidious C toolchain challenges. They're not M1-specific, but they are manifesting on M1 machines.