* file catalog and associated metadata come from SQLite files so listing directories and stating files is fast

* data is chunked and de-duplicated

* catalogues are signed so you can use untrusted HTTP proxies and still ensure integrity

A key difference is that the file system contents is preprocessed into content-addressable storage (somewhat similar to the format in a .git folder). Also a number of features and optimizations to make it work well as a shared software area, which is characterized by many small, often memory-mapped files and a meta-data heavy access pattern.