Do you have access to your very first (production) codebase still?
My very first PHP app was a Snom/Yealink SIP phone configuration tool. Give it a CSV of MAC addresses and auth, and it spits out the .cfg files they would need to auto-boot with their credentials in a given office.
index.php, functions.php, crazy if nesting, template mixed in with the logic! Even built a little admin panel page too.
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