borg-anchor


Borg backups with Bitcoin timestamping. Your data lives on forever.

Overview

borg-anchor combines BorgBackup (deduplicating archiver) with Bitcoin timestamping to create backups with cryptographic proof of existence.

``
Your Data → Borg Backup → Bitcoin Anchor → Immortal Proof
`

Features

- Deduplication - Only store changes, not duplicates
- Compression - Efficient storage with lz4/zstd
- Encryption - Optional AES-256 encryption
- Bitcoin Timestamping - Immutable proof your backup existed
- Chained Proofs - Each backup linked to previous via UTXO chain

Installation

`bash
npm install -g borg-anchor
`

$3

- BorgBackup installed
- blocktrails CLI for Bitcoin anchoring
- Node.js 18+

Quick Start

`bash


Initialize a new backup repository

borg-anchor init ~/backups

Configure your Bitcoin key

cd ~/backups
git config nostr.privkey

Create your first backup

borg-anchor backup ~/mydata --name first-backup

View all projects and backups

borg-anchor info

List backups in current project

borg-anchor list

Verify a backup is anchored

borg-anchor verify first-backup

Restore a backup

borg-anchor restore first-backup /tmp/restore
`

Commands

| Command | Description |
|---------|-------------|
| info | Dashboard of all projects (CLI) |
| dashboard | Web dashboard (localhost:3077) |
| init [path] | Initialize borg repo and config |
| backup | Create backup and anchor on Bitcoin |
| list | List backups and trail status |
| verify | Verify backup is anchored |
| restore [dest] | Restore backup to destination |
| show | Show config and trail status |

Options

$3

| Option | Default | Description |
|--------|---------|-------------|
| --repo | repo | Borg repository directory name |
| --encryption | none | none, repokey, repokey-blake2 |
| --network | tbtc4 | btc (mainnet) or tbtc4 (testnet) |

$3

| Option | Default | Description |
|--------|---------|-------------|
| --name | backup-YYYY-MM-DD | Archive name |
| --no-anchor | - | Skip Bitcoin anchoring |
| --dry | - | Dry run (don't broadcast) |

How It Works

1. Borg creates a deduplicated backup with a unique fingerprint (SHA-256)
2. The fingerprint is anchored on Bitcoin via a chained UTXO trail
3. Anyone can verify the backup existed at the anchored time

`
┌─────────────┐ ┌─────────────┐ ┌─────────────┐
│ Your Files │ ──▶ │ Borg Backup │ ──▶ │ Bitcoin TX │
│ │ │ fingerprint │ │ timestamp │
└─────────────┘ └─────────────┘ └─────────────┘
`

Files

After initialization, your backup directory contains:

`
~/backups/
├── .borg-anchor.json # Configuration
├── .blocktrail.json # Bitcoin trail state
├── .git/ # Git repo (holds keys)
└── repo/ # Borg repository
`

Projects are also registered globally for the dashboard:

`
~/.borg-anchor/
└── projects.json # List of all borg-anchor projects
`

Verification

To verify a backup:

`bash


Get the fingerprint

borg info ~/backups/repo::my-backup | grep fingerprint

Check it's anchored

borg-anchor verify my-backup
`

The fingerprint in your backup must match the fingerprint recorded on Bitcoin.

Networks

| Network | Flag | Use Case |
|---------|------|----------|
| tbtc4 | --network tbtc4 | Testing (free, default) |
| btc | --network btc` | Production (real Bitcoin) |

License

AGPL-3.0

Links

- Documentation
- GitHub
- npm
- BorgBackup
- solid.live