clync

Encrypted sync for Claude Code across machines.

What it does

Claude Code stores conversations, memories, settings, commands, and skills locally in ~/.claude/. clync encrypts all of it with age and syncs it to a storage backend of your choice. When the same session is edited on two machines, clync merges them using the conversation's UUID tree structure instead of overwriting.

Great for backup, and for people using more than one machine.

Features

Install

cargo install clync

With S3 support:

cargo install clync --features s3

Or from source:

git clone https://github.com/Saturate/clync
cd clync
cargo install --path .

Quick start

First machine

clync init

The interactive setup walks you through:

1. Sync repo path
2. Encryption method (key file, passphrase, 1Password, Bitwarden, pass, or none)
3. What to sync (everything by default)
4. Git remote (can create a private GitHub repo via gh cli)
5. First push

Or non-interactive for scripting:

# Git backend with 1Password
clync init --repo ~/.clync/data --onepassword "op://Personal/clync/age-secret-key"

# Local folder (NAS, Dropbox, USB drive)
clync init --storage folder --repo /mnt/nas/clync-data

# No encryption (use a private repo)
clync init --repo ~/.clync/data --no-encrypt

Second machine

# SSH
clync join git@github.com:you/clync-data.git

# or HTTPS
clync join https://github.com/you/clync-data.git

This clones the repo, reads clync.toml to detect the encryption method, asks for the key, and pulls all sessions.

Sync

clync sync       # pull + push (auto git by default)
clync push       # encrypt and push
clync pull       # pull and smart-merge
clync status     # see what's different

Commands

Merge

When both machines edit the same session, clync merges using the conversation structure:

• Each message has a UUID and parent UUID forming a tree
• Messages unique to one side are included
• Same UUID with different content: newer timestamp wins
• Non-UUID entries (metadata) are deduplicated

No data is lost. Both machines' messages are preserved.

Encryption

Six modes, pick during clync init:

The age secret key is never stored in the sync repo. With password managers, the key syncs automatically across machines.

Storage backends

Git (default)

Syncs through a git repo with optional remote. Supports LFS for large sessions.

[sync.storage]
type = "git"
path = "~/.clync/data"
auto_push = true
lfs_threshold = 103809024  # 99MB, 0 to disable

Folder

Syncs to any local or network-mounted path. No git needed.

[sync.storage]
type = "folder"
path = "/mnt/nas/clync-data"

S3 (requires --features s3)

Syncs to any S3-compatible service: AWS, Cloudflare R2, MinIO, DigitalOcean Spaces, Backblaze B2.

[sync.storage]
type = "s3"
bucket = "my-clync-bucket"
region = "eu-west-1"
prefix = "clync/"
endpoint = "https://my-minio.example.com"  # omit for AWS

Credentials from environment (AWS_ACCESS_KEY_ID/AWS_SECRET_ACCESS_KEY) or config (access_key/secret_key).

Note: S3 has no native locking. If multiple machines sync concurrently, writes can conflict. Use git or folder backends for multi-machine setups, or coordinate S3 access externally.

Configuration

Config lives at ~/.config/clync/config.toml:

[sync]
claude_dir = "~/.claude"

[sync.storage]
type = "git"
path = "~/.clync/data"
auto_push = true

[encryption]
method = "onepassword"
reference = "op://Personal/clync/age-secret-key"

[targets]
sessions = true
memories = true
settings = true
commands = true
skills = true
global_claude_md = true

The sync repo also contains a plaintext clync.toml with the encryption method and targets, so clync join knows what to expect.

MCP server

Add to your Claude Code MCP config:

{
  "mcpServers": {
    "clync": {
      "command": "clync",
      "args": ["mcp"]
    }
  }
}

Tools: list_sessions, session_detail, sync_status, sync_push, sync_pull, sync_log, config_show, help

Sync repo structure

clync.toml              # plaintext metadata (encryption method, targets)
README.md               # auto-generated
manifest.json.age       # encrypted session index (or .json if unencrypted)
sync.log.jsonl          # plaintext sync history
sessions/
  <uuid>.jsonl.age      # encrypted session files
extras/
  settings.json.age     # encrypted settings
  CLAUDE.md.age         # encrypted global instructions
  commands/             # encrypted custom commands
  skills/               # encrypted custom skills
memories/
  <project>/            # encrypted project memories (normalized paths)

Contributing

See CONTRIBUTING.md for development setup, changeset workflow, and project structure.

License

MIT