Like many, I tried to leave reddit a while back. Remember when everyone was boycotting when they killed their third party app API? Well yeah, I tried and failed. However, during that time I explored Lemmy, and later, PieFed. If you dont know what they are, here is a blog post that does a good job explaining them.
I've been a regular user of PieFed for a while, and although there is at least 4 different "unixporn' communities all fighting for superiority, there was no unixart. So i decided to create one: https://piefed.social/c/unixart -- It's the first, but it may not be the last.
I've written a python script that I have running on a server every 12 hours via a cron job that scraps recent posts of r/unixart and posts them on c/unixart. It's doesn't really handle video/gif and multi-image posts well, but otherwise it works.
I haven't tried to implement a reverse mirror yet (pifed > reddit) but this is also possible. I'll only consider that if c/unixart gets some traffic of it's own and it's of equal quality.
All posts on the mirror community are posted by my moderator account, but reddit usernames are taged in the footer of each post for author credit.