This and https://wiki.bash-hackers.org, #bash on irc (libera now) helped me tremendously on writing hardened scripts in production.

nice thanks for sharing!

https://github.com/dylanaraps/pure-bash-bible

>The goal of this book is to document commonly-known and lesser-known methods of doing various tasks using only built-in bash features. Using the snippets from this bible can help remove unneeded dependencies from scripts and in most cases make them faster.

Interesting, although on a quick skimming most of the functions listed there are wrappers over... printf?