Ask HN: Software to share your library with friends?

I and some friends would like to set up a shared library program where we can see the contents of each other's bookshelves and then borrow books from each other easily. I was looking around for suitable software; TinyCat looks reasonable but I'm not sure if it's the perfect solution to this problem. Do you have any recommendations?

I'm happy to self host but that's not a requirement. Bonus points for good FOSS solutions.

Edit: in case you're wondering, I'm talking about physical dead-tree books, not ebooks.