[hammerandtongs]

If this were designed to seamlessly interoperate with Calibre (a filesystem and sqlite3 iirc) this would be potentially useful to me.

I could more confidently selfhost a web version of my calibre library for reading and bookmarking. Calibre has a web version but I'm not confident in it and would be uninclined to host it even in a sandstorm instance for example.

The memory issues of libreread, as indicated by others, are too much for hosting in a friendly way with other apps. The value of full text search isn't nearly good enough to warrant the memory usage. Aim for < 60MB serverside.

Calibre has an large amount of features that are critical for people actually trying to maintain an ebook library. Those features have been added and polished over a decade. I'm very doubtful they can be replicated in a reasonable timeframe.

Valuable to see people making things in this area though! Cheers.