zsh is generally wonderful, and it's sufficiently like bash/POSIX sh that it works.
However, it uses 1-indexed arrays, whereas bash uses 0-indexed arrays. This totally caught me out.
Choosing a syntax for a new programming language is hard. You want to be similar enough to an established language to avoid scaring off users.
You still want to be sufficiently novel to be recognisable. Which languages do this well?
What's your favourite file checksum when you don't need cryptographic strength?
md5sum is convenient (it's installed on most systems), but it was originally intended to be secure. I just want a fast content check.
(Or is sha256sum sufficiently optimised that it doesn't matter?)