Brilliant pointers! Thanks to metacpan and this amazing fellow ( https://cpan.metacpan.org/authors/id/J/JH/JHI/ ) who's kept antique source alive, I was able to build a working test version with no dramas (perl5.7.3 being the documented last time this worked)

2023/11/12 12:17.12   1,065,256   microperl
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That's on my 64bit intel; a 32bit build for xtensa would presumably be even smaller... which leaves at least 600kb space to implement the OS-replacement stuff if I wanted to ship something even smaller than micropython :-)

I apparently only need to implement these:

- <stddef.h>, <stdlib.h>
- rename()
- opendir(), readdir(), closedir() (via dirent.h)
- memchr(), memcmp(), memcpy(), memset() (via string.h)
- (a safe) putenv() (via stdlib.h)
- strtoul() (via stdlib.h)

$ ./microperl -v

This is perl, v5.7.3 built for unknown

Copyright 1987-2002, Larry Wall
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