> I struggle to find anything on this post that wouldn't be caught by some kind of unit test or manual review, especially when comparing with the GNU source for the coreutils.

> If you do a rewrite, you should fully understand and learn from the predecessor, otherwise youre bound to repeat all the mistakes. Embarassing.

Interestingly, the uutils project uses the GNU coreutils test suite.

EDITED to add: they also have a stated position of not allowing contributions based on reading the GPL'd source.