zub

A git-like content-addressed store for filesystem trees.

what it is

zub stores directory trees as content-addressed objects (blobs, trees, commits) with full metadata preservation: ownership, permissions, xattrs, sparse files, and hardlinks.

Similar to ostree's bare repo mode, blobs are stored uncompressed with metadata applied directly to the files, enabling hardlink-based checkout for zero-copy extraction.

why

• simpler than ostree
• supports user namespace remapping (rootless containers)
• union merging for layer composition
• efficient deduplication via content-addressing

install

cargo install zub-store

build

# static binary via container (no dependencies needed)
make build

# or locally
cargo build --release

usage

# init a repo
zub init /path/to/repo

# repo is auto-detected from ZUB_REPO env or .zub symlink/dir
ln -s /path/to/repo .zub
# or
zub init .zub

# commit a directory tree
zub commit /some/dir my-ref -m "initial"

# checkout (hardlinks by default)
zub checkout my-ref /target/dir

# view history
zub log my-ref

# diff two refs
zub diff ref-a ref-b

# merge multiple refs (last-wins on conflict)
zub union ref-a ref-b ref-c merged-ref --on-conflict last

# sync between repos (local or SSH)
zub push /other/repo my-ref
zub pull user@host:/remote/repo some-ref  # auto-deploys zub if needed

commands

Run zub --help for full command list.

repository layout

repo/
├── config.toml
├── objects/
│   ├── blobs/      # file content (uncompressed, with metadata)
│   ├── trees/      # directory structure (cbor + zstd)
│   └── commits/    # commit metadata (cbor + zstd)
└── refs/
    ├── heads/
    └── tags/

license

MIT