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Dolt Backend for Beads

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Dolt Backend for Beads

Beads uses Dolt as its storage backend. Dolt provides a version-controlled SQL database with cell-level merge, native branching, and two deployment modes.

Why Dolt?

  • Native version control — cell-level diffs and merges, not line-based
  • Multi-writer support — server mode enables concurrent agents
  • Built-in history — every write creates a Dolt commit
  • Native branching — Dolt branches independent of git branches
  • Single-binary option — embedded mode for solo users (no server needed)

Getting Started

New Project

bash
# Embedded mode (single writer, no server — default for standalone)
bd init

# Server mode (multi-writer, e.g. orchestrator)
gt dolt start           # Start the Dolt server
bd init --server        # Initialize with server mode

Migrate from SQLite (Legacy)

If upgrading from an older version that used SQLite:

Note: The bd migrate --to-dolt command was removed in v0.58.0. For pre-0.50 installations with JSONL data, use the migration script:

bash
scripts/migrate-jsonl-to-dolt.sh

See Troubleshooting if you encounter connection errors after migration.

Migration creates backups automatically. Your original SQLite database is preserved as beads.backup-pre-dolt-*.db.

Modes of Operation

Embedded Mode (Solo / Standalone)

In-process Dolt engine — no separate server needed. This is the default for standalone Beads users. The bd binary includes everything; just bd init and go.

  • Single-writer (one process at a time)
  • Data lives in .beads/dolt/ alongside your code
  • Push to GitHub with bd dolt push — code and issues in one repo
  • Zero ops: no server, no ports, no PID files

Server Mode (Multi-Writer / Orchestrator)

Connects to a running dolt sql-server for multi-client access.

bash
# Start the server (orchestrator)
gt dolt start

# Or manually
cd ~/.dolt-data/beads && dolt sql-server --port 3307
bash
# Initialize in server mode
bd init --server

# Or switch via environment variable
export BEADS_DOLT_SERVER_MODE=1
yaml
# .beads/config.yaml (server mode settings)
dolt:
  mode: server
  host: 127.0.0.1
  port: 3307
  user: root

Switch to server mode when you need:

  • Multiple agents writing simultaneously
  • Orchestrator multi-rig setups
  • Federation with remote peers

Migrating Between Backends

You can migrate data between embedded mode and server mode using bd backup. Both directions preserve full Dolt commit history.

Server → Embedded

  1. Create a backup from the server-mode project:

    bash
    # In the server-mode project directory
bd backup init /path/to/backup-dir
bd backup sync

  2. Create a new embedded-mode project and restore:

    bash
    mkdir new-project && cd new-project
bd init                  # creates an embedded-mode project by default
bd backup restore --force /path/to/backup-dir

    --force overwrites the freshly-initialized database with the backup contents. The restore automatically:

    • Updates metadata.json to match the restored project identity
    • Registers the backup directory for future bd backup sync
    • Backfills the embedded migration tracker (schema_migrations)

  3. Verify:

    bash
    bd list
bd backup status

Embedded → Server

  1. Create a backup from the embedded-mode project:

    bash
    # In the embedded-mode project directory
bd backup init /path/to/backup-dir
bd backup sync

  2. Create a new server-mode project and restore:

    bash
    mkdir new-project && cd new-project
bd init --server         # creates a server-mode project
bd backup restore --force /path/to/backup-dir

  3. Verify:

    bash
    bd list
bd backup status

Backup Commands Reference

CommandDescription
bd backup init <path>Register a backup destination (filesystem or DoltHub URL)
bd backup syncPush database to the configured backup destination
bd backup restore [path]Restore from a backup directory (--force to overwrite)
bd backup removeUnregister the backup destination
bd backup statusShow backup configuration and last sync time

Notes

  • Data locations differ between modes: .beads/embeddeddolt/ (embedded) vs .beads/dolt/ (server)
  • The backup directory is a full Dolt backup — it can be on a local drive, NAS, or DoltHub
  • You can also migrate via Dolt remotes (bd dolt push / bd dolt pull) if both projects share a remote

See also DOLT-BACKEND.md.

Federation (Peer-to-Peer Sync)

Federation enables direct sync between Dolt installations without a central hub.

Architecture

┌─────────────────┐         ┌─────────────────┐
│  Workspace A    │◄───────►│  Workspace B    │
│  dolt sql-server│  sync   │  dolt sql-server│
│  :3306 (sql)    │         │  :3306 (sql)    │
│  :8080 (remote) │         │  :8080 (remote) │
└─────────────────┘         └─────────────────┘

In federation mode, the server exposes two ports:

  • MySQL (3306): Multi-writer SQL access
  • remotesapi (8080): Peer-to-peer push/pull

Quick Start

bash
# Add a peer
bd federation add-peer town-beta 192.168.1.100:8080/beads

# With authentication
bd federation add-peer town-beta host:8080/beads --user sync-bot

# Sync with all peers
bd federation sync

# Handle conflicts
bd federation sync --strategy theirs  # or 'ours'

# Check status
bd federation status

Topologies

PatternDescriptionUse Case
Hub-spokeCentral hub, satellites sync to hubTeam with central coordination
MeshAll peers sync with each otherDecentralized collaboration
HierarchicalTree of hubsMulti-team organizations

Credentials

Peer credentials are AES-256 encrypted, stored locally, and used automatically during sync:

bash
# Credentials prompted interactively
bd federation add-peer name url --user admin

# Stored in federation_peers table (encrypted)

Troubleshooting

bash
# Check federation health
bd doctor --deep

# Verify peer connectivity
bd federation status

Contributor Onboarding (Clone Bootstrap)

When someone clones a repository that uses Dolt backend:

  1. Run bd bootstrap in the clone
  2. If the git remote has refs/dolt/data (pushed via bd dolt push), bd bootstrap auto-detects it and clones the database from the remote
  3. Work continues normally — all existing issues are available

No manual steps required beyond bd bootstrap. The auto-detect:

  • Probes origin for refs/dolt/data
  • Clones the Dolt database from the remote (instead of creating a fresh one)
  • Configures the Dolt remote for future bd dolt push/pull

If sync.remote is set in .beads/config.yaml, that takes precedence over auto-detection. Any Dolt-compatible remote URL is supported (DoltHub, S3, GCS, file, or git). bd init will warn if it detects refs/dolt/data on origin and suggest using bd bootstrap instead.

Verifying Bootstrap Worked

bash
bd list              # Should show issues
bd vc log            # Should show initial commit

Troubleshooting

Server Not Running

Symptom: Connection refused errors when using server mode.

failed to create database: dial tcp 127.0.0.1:3307: connect: connection refused

Fix:

bash
gt dolt start        # Orchestrator command
# Or
gt dolt status       # Check if running

Bootstrap Not Running

Symptom: bd list shows nothing on fresh clone.

Check:

bash
ls .beads/dolt/            # Should NOT exist (pre-bootstrap)
BD_DEBUG=1 bd list         # See bootstrap output

Force bootstrap:

bash
rm -rf .beads/dolt         # Remove broken state
bd list                    # Re-triggers bootstrap

Database Corruption

Symptom: Queries fail, inconsistent data.

Diagnosis:

bash
bd doctor                  # Basic checks
bd doctor --deep           # Full validation
bd doctor --server         # Server mode checks (if applicable)

Recovery options:

  1. Repair what's fixable:

    bash
    bd doctor --fix

  2. Rebuild from remote:

    bash
    rm -rf .beads/dolt
bd list                  # Re-triggers bootstrap

Lock Contention (Embedded Mode)

Symptom: "database is locked" errors.

Embedded mode is single-writer (enforced via file lock). If you need concurrent access, switch to server mode. See Migrating Between Backends.

Configuration Reference

yaml
# .beads/config.yaml

# Dolt settings
dolt:
  # Auto-commit Dolt history after writes (default: on for embedded, off for server)
  auto-commit: on        # on | off

  # Storage mode (default: embedded)
  mode: embedded         # embedded | server
  # Server mode settings (only used when mode: server)
  host: 127.0.0.1
  port: 3307
  user: root
  # Password: env var or credentials file (see below)

  # Shared server mode (GH#2377): all projects share a single Dolt server
  # at ~/.beads/shared-server/. Each project uses its own database (prefix-based).
  # Eliminates port conflicts and reduces resource usage on multi-project machines.
  shared-server: false   # true | false

  # Idle auto-stop timeout for the Dolt server (default: "30m", "0" disables)
  idle-timeout: 30m

Environment Variables

VariablePurpose
BEADS_DOLT_PASSWORDServer mode password (highest priority)
BEADS_CREDENTIALS_FILEPath to credentials file (overrides default location)
BEADS_DOLT_SERVER_MODEEnable server mode (set to "1")
BEADS_DOLT_SERVER_HOSTServer host (default: 127.0.0.1)
BEADS_DOLT_SERVER_PORTServer port (default: 3307, or 3308 in shared mode)
BEADS_DOLT_SERVER_TLSEnable TLS (set to "1" or "true")
BEADS_DOLT_SERVER_USERMySQL connection user
BEADS_DOLT_SHARED_SERVEREnable shared server mode (set to "1" or "true")
DOLT_REMOTE_USERPush/pull auth user
DOLT_REMOTE_PASSWORDPush/pull auth password
BD_DOLT_AUTO_COMMITOverride auto-commit setting

Credentials File

For multi-server setups, you can store passwords in an INI-style credentials file instead of juggling environment variables per project. Passwords are looked up by [host:port] section, so each project automatically gets the right password based on its configured server.

Password resolution order:

  1. BEADS_DOLT_PASSWORD env var (highest priority, existing behavior)
  2. Credentials file lookup by [host:port] (using the resolved runtime port)
  3. Empty string (no password)

Port resolution note: The [host:port] used for credential lookup matches the resolved runtime port (from the port file, env var, or config — in that priority order), not necessarily the port stored in metadata.json. This matters when using IAP tunnels: if your tunnel maps remote:3307 to localhost:3308, store your password under [127.0.0.1:3308] and the credentials file will match the actual connection.

Default location: ~/.config/beads/credentials (Linux/macOS), %APPDATA%\beads\credentials (Windows)

Override location: Set BEADS_CREDENTIALS_FILE env var.

File format:

ini
# ~/.config/beads/credentials
[127.0.0.1:3307]
password=localDevPassword

[beads.company.com:3307]
password=teamServerPassword

[10.0.1.50:3308]
password=officePassword

Permissions: On Linux/macOS, a warning is printed to stderr if the file is readable by group or others (mirrors ssh behavior). Set permissions with:

bash
chmod 600 ~/.config/beads/credentials

Dolt Version Control

Dolt maintains its own version history, separate from Git:

bash
# View Dolt commit history
bd vc log

# Show diff between Dolt commits
bd vc diff HEAD~1 HEAD

# Create manual checkpoint
bd vc commit -m "Checkpoint before refactor"

Auto-Commit Behavior

In embedded mode (standalone default), each bd write command creates a Dolt commit:

bash
bd create "New issue"    # Creates issue + Dolt commit

In server mode (orchestrator), auto-commit defaults to OFF because the server manages its own transaction lifecycle. Firing DOLT_COMMIT after every write under concurrent load causes 'database is read only' errors.

Override for batch operations (embedded) or explicit commits (server):

bash
bd --dolt-auto-commit off create "Issue 1"
bd --dolt-auto-commit off create "Issue 2"
bd vc commit -m "Batch: created issues"

Server Management (Orchestrator)

The orchestrator provides integrated Dolt server management:

bash
gt dolt start            # Start server (background)
gt dolt stop             # Stop server
gt dolt status           # Show server status
gt dolt logs             # View server logs
gt dolt sql              # Open SQL shell

Server runs on port 3307 (avoids MySQL conflict on 3306).

Shared Server Mode

On machines with multiple beads projects, each project normally starts its own Dolt server. Shared server mode runs a single Dolt server at ~/.beads/shared-server/ that serves all projects:

bash
# Enable for this project
bd dolt set shared-server true

# Or enable machine-wide via environment variable
export BEADS_DOLT_SHARED_SERVER=1

# Or enable during init
bd init --prefix myproject --shared-server

Benefits:

  • No port conflicts between projects (single server on port 3308, avoids orchestrator on 3307)
  • Reduced resource usage (one process instead of many)
  • Automatic database isolation (each project uses its own database name)

How it works:

  • Server state files (PID, port, lock, log) live in ~/.beads/shared-server/
  • Dolt data directory: ~/.beads/shared-server/dolt/
  • Each project's database is stored as a subdirectory (e.g., ~/.beads/shared-server/dolt/myproject/)
  • The file lock mechanism ensures safe concurrent access from multiple projects
  • Default port is 3308 (not 3307) to avoid conflict with the orchestrator. Override with BEADS_DOLT_SERVER_PORT or dolt.port in config.yaml

Important: Each project on a shared server must have a unique prefix (database name). Two projects with the same prefix share the same database — if this happens accidentally, the project identity check will detect the mismatch and refuse to connect, preventing silent data corruption. Always use distinct prefixes when running bd init --shared-server.

bash
# Check shared server status from any project
bd dolt status

# Show full configuration including shared mode
bd dolt show

Data Location (Orchestrator)

<town-root>/.dolt-data/
├── hq/                  # Town beads (hq-*)
├── my-project/          # Project rig (mp-*)
├── beads/               # Beads rig (bd-*)
└── other-project/       # Other rig (op-*)

Migration Cleanup

After successful migration from SQLite, you may have backup files:

.beads/beads.backup-pre-dolt-20260122-213600.db
.beads/sqlite.backup-pre-dolt-20260123-192812.db

These are safe to delete once you've verified Dolt is working:

bash
# Verify Dolt works
bd list
bd doctor

# Then clean up (after appropriate waiting period)
rm .beads/*.backup-*.db

Recommendation: Keep backups for at least a week before deleting.

See Also