My e-book management currently consist of storing a bunch of files, both .epub, .pdf and .azw3 stored either by author (fiction) or by topic (non-fiction), for various sources (purchased e-books, downloaded via University subscriptions, Project Guthenberg and some from Library Genesis/Anna’s Archive). For some time I’d been wanting to organize them better, with a web UI to download in a format of my choice and to be able to share with others.