I feel like it should be the job of the filesystem to maintain an index and incrementally update it whenever files are created or removed, but afaict no modern filesystem offers it.
The background indexing does get bogged down when there’s a massive number of file changes, so I exclude things like “node_modules” folders. It also indexes the actual content of text files and not just filenames.
Sadly the CLI interface for `mdfind` is incredibly obtuse and verbose, and very under documented [0]. When querying anything besides just a filename I still have to lookup the correct incantation. For example, here's how to do a case insensitive search for any folder containing "apple" modified in the last year:
mdfind 'kMDItemDisplayName = "*apple*"c && kMDItemFSContentChangeDate <= $time.today(-365) && kMDItemKind == "Folder"'
Compare that to fd:
fd --changed-within=1y -t d -i apple
I've thought about just making a simpler shell script that turns a valid `fd` query into the obscure `mdfind` incantation. And you can use `-onlyin ...` to limit the search to a particular dir just like fd/find. Might get around to it!
We already pretend files are on the physical disk and sync it in the background. Adding smarter indexing to that shouldn't be a huge deal.