At this branch:

https://github.com/gambiteer/srfi-231/tree/231-bis?tab=readme-ov-file

I've now committed a "minimal" implementation with no specialized code
or error checking, and a test program that can be used to test both the
small and regular implementations.

The stripped-down routines in the minimal implementation suggest to me
the intrinsic complexity of each routine.  `array-reshape`, which did
not simplify at all, is the most complex and `array-tile` and
`array-block` are of moderate complexity.

Brad