Regarding recommendations similar to Ra, it's not exactly the same thing, but https://unsongbook.com/ is fantastic and has a similar flavor I think.
The religious references on the actual website (and lack of much real explanation) made it very difficult for me to give it a chance, but I looked it up a bit and it seems like there is more to it than that, so maybe I'll give it a try.
edit: reading the first chapter definitely changed my first impression. It definitely has many similarities to qntm's writing. I will certainly be reading more...
“STOP TRYING TO UNDERSTAND THE WILL OF GOD,” said Uriel. “IT NEVER HELPS.” --the archangel Uriel
> "Are you all right?" Sohu finally asked.
> "I WAS TRYING TO WIGGLE MY EARS."
> Sohu wiggled her ears again.
> "YOU ARE VERY INTERESTING."
> "So will you teach me the kabbalah?"
> "NO."
it's so cute!! I love this
also, I love how many references it makes to actual programming; it's always hilarious to see Uriel explaining code bugs in reality.
(also, I liked Antimemetics, but not Ra, so I will just say I think unsong is leaps and bounds better than Ra)