@jarulf I'm using Openreads, it's not self hosting, but it's private, no socials, free/open source software, it's a mobile app. If you change mobile phones, you'll need to export, backup, and import into the new one.
It can add books by scanning the ISBN, it divides books by reading, for later, finished. It captures days of reading, it allows you to take notes, give stars, insert number of pages. It also gives us statistics, how many books we read, the book we took more/less time to read, number of pages read, by year, by month, etc. it also allows tagging to tell if it's paperbook, audiobook, eBook. I also use tags to tell if it's a library book or a book I own.
If you decide not to self host, maybe it can be of interest.
(I also use a paper reading journal for my notes, reviews when the books ask for them, an excuse to writing by hand, but this more practical information stays in Openreads)

Link to features and stores to download:
https://github.com/mateusz-bak/openreads

@wil @bookstodon