Arqfs implements a file system interface to a collection of Arq backups.

usage: arqfs [-m mtpt]

Arqfs mounts the Arq backups on the file system directory mtpt, (default /mnt/arq). The directory must exist and be writable by the current user.


Arq is an Amazon S3-based backup system for OS X and sold by Haystack Software ( This software reads backups written by Arq. It is not affiliated with or connected to Haystack Software.


Arqfs reads necessary passwords from the OS X keychain. It expects at least two entries:

The keychain entry for should list the Amazon S3 access ID as user name and the S3 secret key as password.

Each backup being accessed must have its own keychain entry for host, listing the backup UUID as user name and the encryption password as the password.

Arqfs will not prompt for passwords or create these entries itself: they must be created using the Keychain Access application.


Arqfs creates a virtual file system using the FUSE file system layer. On OS X, it requires OSXFUSE (


Reading the Arq backups efficiently requires caching directory tree information on local disk instead of reading the same data from S3 repeatedly. Arqfs caches data downloaded from S3 in $HOME/Library/Caches/arq-cache/. If an Arq installation is present on the same machine, arqfs will look in its cache ($HOME/Library/Arq/Cache.noindex) first, but arqfs will not write to Arq's cache directory.


Arqfs only runs on OS X for now, because both FUSE and the keychain access packages have not been ported to other systems yet.

Both Arqfs and the FUSE package on which it is based have seen only light use. There are likely to be bugs. Mail with reports.

Source Files