Microblog.pub is a lightweight self-hosted single user Fediverse server which can be followed from Mastodon etc.
You can find out more info at:
The official account disappeared for a while but it's now back at:
As the account notes, it's just been rewritten with version 2.0 of the software, so you may need to unfollow and then refollow.
(Having said that, I haven't been able to actually follow the account, it seems to work at first but then gives a "follow request" message? Have you managed to get this to work?)