Relational Filesystem


This is a linux userspace filesystem using fuse and a relational database to store information about files. Special directories can represent views on the database, and many powerful features, such as bayesian classification, are added through plugins.

The idea is very common among computer users nowadays, but no free software implementation exists yet; the main reason to use such a thing, which certainly adds overhead to common file operations, is that often it's easier to find stuff on Google than on our hard drives. Giving users the full power of a relational database, which over years has proved to be simple enough to be understood by any kind of people, at least at the query level, will help exploiting one's own CPU for something better than a screensaver.

The project is hosted at sourceforge here:


RelFS is in pre-alpha stage right now, if you download it expect more bugs than features. If you are a developer, or are interested in a preview of RelFS, you can either check out the most recent version from CVS at

or get a binary release for some linux distributions here

README and Frequently Asked Questions

The README for the project is here, while the FAQ are here.

Links and Credits

The main ingredients of the RelFS cocktail are:

Fuse, “Filesystem in User Space”, without it RelFS would never have seen the light:

OCaml, the programming language of choice for discriminating hackers:

OCamlFuse, the interface between Fuse and OCaml:, written by me.

Markus Mottl's home page – he is the mantainer of various libraries used in RelFS:

Gerd Stolpmann's site about Objective Caml: and the very good tools ocamlfind and GODI.

PostgreSQL, the robust, complete, free RDBMS used in RelFS:

Authors and Contributors

The main autor of RelFS is... well, it's me: I am Vincenzo Ciancia, a Ph.d. student at the University of Pisa. I can be reached via e-mail as ciancia at or applejack at

Patch contributors can be found in the AUTHORS file available here. So far, the only contributor was Michael Raskin, fb08af68 at, who deserves a special mention since he learned OCaml for the occasion “more than doubled his skills in Ocaml” :-) and also was the only one, besides me, believing in the project before the conquest of the world.

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