So you're a doomsday prepper and you intend to throw a few dollars at a multi TiB "restart civilization" digital book library with a few million books, a few laptops and some solar cells to power them. How best to hierarchically organise the group/ community doomsday digital book library? Say 5 million books, each in its own directory (for any cover art, PDF and or text versions of the book, perhaps audio, code, etc). Debian has ~40K packages, and divides these into {a..z}* and lib{a..z}*, for roughly 60 "top level" directories. Each package has its subdirectory in one of these. The largest directories are at about 2K to 3K entries (subdirectories). However, when prepping for a few million books, we have around 1000 times as many "packages"/books to store, which could mean e.g. 50,000 or more in the popular s directory for example - probably a little more than is sane. "Formal" library software (e.g. Evergreen) may be the answer for repo wide searchability of meta data, but when others share interest, they may only be able to store, and or may be only particularly interested in a sub-category or two such as health and agriculture/gardening, so it might be best anyway to use a handful of top level "general categories" to reduce our maximums down from 50K books per dir, to 10 fold fewer at least. Has anyone done anything like this, and if so, how did you solve it? (Medium term, the problem begs for a git-like addressed, git-like P2P addressable/verifiable "content management" solution; e.g. if I have a random collection of say 10K books, it would be nice to be able to say something like: git library init # add my books: git add . git commit git library sort categories git library add index1 # create an "indexing" branch git commit # add some upstream/p2p libraries for indexing/search/federation: git library index add upstream:uni.berkely git library p2p add i2p.tunnel:myfriend.SHA git library full-index pull myfriend.SHA git library math-index pull myfriend.SHA git library book:SHA pull myfriend.SHA ) Perhaps this has not been really done before?