If you want to test that the old way to write a C extension, with static types and global variables, still work, IMO it should be another module than this "template".

We could adjust the wording in the top of the file, and also rename it to something like xxlegacy.c. But I think this warrants a broader discussion :)

IMO it should be a show case of the best practice to write a C extension in 2022. Otherwise, people will continue to copy/paste this old code and will propagate static types and other legacy code to their project :-(

That's what the xxlimited.c module is :)