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-# A fake file-system implemented as a set of named blob tuples.
+# A post-UNIX storage layer
+
+This repository hosts a proof-of-concept storage system and synthetic file- 
+system frontend for the Genode OS framework. The concept of the *file* has been 
+replaced with the *blob*, a finite and linear stream of bytes. Blobs are 
+identified by 256 bit hash digests using BLAKE2B in tree mode.
+
+A *blobset* is flat map of key hashes to blob hashes. Key hashes are 64 bits so
+the practical limit to the number of set members is 2^32. Sets are implemented as 
+lazy-loaded [hash array mapped tries](https://en.wikipedia.org/wiki/Hash_array_mapped_trie)
+with a 64 node fan-out. A *store* contains both data blobs and blobs of set 
+metadata and is the public API to both blobs and sets.
+
+Two stores are provided, one that stores blobs to a UNIX file-system backend and 
+the other as a HTTP client. A primitive HTTP server is provided to serve the 
+UNIX backend to the client. A Lisp-like REPL is provided to build and explore 
+sets and a Genode file-system server is provided to serve sets as file-systems.
+
+Exposing a set as a UNIX file-system is trivial because set keys are hash 
+digests of arbitrary byte-strings, so names containing the */* character may be 
+mapped in the set.
+
+## Storing music
+A plugin for the [Picard](https://picard.musicbrainz.org/) tagger is available 
+at _extras/picard_plugin_. This plugin ingests audio files into a rolling set 
+and indexes them by [MusicBrainz recording UUID](https://musicbrainz.org/doc/Recording).
+A simple playlist generator for playing these files may be found at
+https://github.com/ehmry/musicbrainz_playlist_generator.