The Compete File System (CFS) is a file management and file system virtualization software layer and Unix command set. CFS provides a framework for distributing files across multiple file systems while allowing the end-user or software developer the convenience of viewing the multiple systems as though they were a single large file system. Internally, CFS uses load balancing and server scheduling algorithms to provide maximum file system space availability while maintaining file server performance. CFS provides this functionality while still remaining in user application space - modifications to the operating system kernel are not necessary, and CFS never needs to operate in kernel or protected mode. In fact, to the extent that the underlying physical file systems can map to the local host's file system, CFS is largely system and platform independent.

CFS is written entirely in Python. The ability to develop high quality code extremely rapidly using Python combined with the depth and sophistication of the Python runtime system allowed a very small team to create this powerful system-level software package very quickly.