Yes - I wrote a messageboard in PHP 18 years ago whilst clutching an OReilly book in my hand.
It's definitely not well coded, but it works.
It's moved servers many times, changed OS, Webserver - and it's now running on my NAS.
I've maybe twice had to spend an afternoon tightening it up due to some PHP change - but broadly been maintenance/issue free.
For at least the last decade I've been pondering re-implementing it in some fancy new language - but as it just keeps working, it slides down the priority list.