Fuse filesystem backed by backblaze cloud storage and transparent local persistent hard-drive cache.

Ideally, it feels like an infinite local file system because it keeps those files local that are used while moving those files to the remote storage that haven't been accessed in a long time.

State of Development


There are a few known issues and race conditions. For example, the ctime on the files may be newer than the correct value. Also, writes and reads are slow.
Do not use in production.

However, the code is a mess and needs to be refactored and cleaned up significantly.

This, in turn, requires better test coverage. Thus, the next step to improve this software is by extending test coverage.


Create a config.yml:

accountId: [...]
applicationKey: [...]
bucketId: [...]
sqliteFileLocation: [...]
targetDiskUsage: [...]

and save in ~/.config/zero/

Here, accountId, applicationKey and bucketId are the corresponding backblaze settings and sqliteFileLocation is simply the path to a place where the sqlite databases containing the state of the virtual file system can be stored.
targetDiskUsage is the amount of disk space (in GB) that you would like to use for local caching.

Install with python develop



zero-fuse <mountpoint> <cache-location>

to mount the file system.
You will also need to run

zero-worker <cache-location>

to start the worker process that moves files between disk and cloud.


Run the tests with pytest like this:

There are 3 categories of tests:

  • Unit tests are testing the code on the function level
  • Integration tests are testing the interactions between bigger parts of the code and outside APIs. They may use the internet.
  • System tests are testing the software as a black box. They should continue working through a big refactor or even if everything was re-written in a different programming language. (There are no system tests yet as of now.)