borg-anchor
Borg backups with Bitcoin timestamping
$ npm install -g borg-anchor
Your Data
→
Borg Backup
→
Bitcoin Anchor
→
Immortal Proof
Deduplication
Only store changes, not duplicates. Second backup of same data? Just bytes.
Bitcoin Timestamping
Immutable proof your backup existed at a specific point in time.
Chained Proofs
Each backup links to previous via UTXO chain. Fully reconstructable.
Optional Encryption
AES-256 encryption with repokey. Your data stays private.
Quick Start
# Initialize backup repository
borg-anchor init ~/backups
# Configure Bitcoin key
cd ~/backups
git config nostr.privkey <your-hex-key>
# Create and anchor backup
borg-anchor backup ~/mydata --name first-backup
# Verify it's on Bitcoin
borg-anchor verify first-backupCommands
| Command | Description |
|---|---|
init [path] | Initialize borg repo and config |
backup <source> | Create backup and anchor on Bitcoin |
list | List backups and trail status |
verify <archive> | Verify backup is anchored |
restore <archive> [dest] | Restore backup to destination |
show | Show config and trail status |
How It Works
- Borg creates a deduplicated, compressed backup with a unique fingerprint (SHA-256)
- The fingerprint is committed to Bitcoin via a chained UTXO trail
- Anyone can verify the backup existed at the anchored time
The Bitcoin transaction proves your data existed before the block timestamp. No trust required - just math.
Networks
| Network | Flag | Use Case |
|---|---|---|
| Testnet4 | --network tbtc4 | Testing (free, default) |
| Mainnet | --network btc | Production (real Bitcoin) |