Fabric

Fabric

Use fabric as a local socket facade for trusted cross-machine services. Keep iroh addresses, QUIC, relays, and peer authorization inside Fabric; consumers should only connect to the local Unix socket or TCP listener returned by fabric dial.

Install

Install a release on macOS or Linux:

curl -sSf https://raw.githubusercontent.com/compoundingtech/fabric/main/install.sh | sh
fabric --version

Expect the binary at ~/.local/bin/fabric unless FABRIC_BIN_DIR or BIN_DIR overrides it. Add that directory to PATH when necessary.

For a source checkout, run ./install.sh, make install, or cargo install --path .. Use cargo run -- <command> without installing during development.

Connect Two Machines

Use the same Fabric release on both machines.

1. Run fabric id on each machine.
2. Exchange the two stable NodeIDs over a trusted channel.
3. Write each remote NodeID to the local authoritative peers.toml as an [[peers]] entry with required id and optional unique name.
4. Run fabric up on both machines. Use fabric reload-peers instead when the daemon is already running.
5. Run fabric status and fabric ping <peer-name> on each machine.

Require mutual allow-list entries. A remote daemon rejects a NodeID that is not in its own peer config even when the dialing machine trusts it.

Treat fabric add <nodeid> [name] as a convenience writer, not a provisioning requirement. Automated provisioning should install the complete peer file.

Treat a successful pong as the basic connection check. It reports round-trip latency and, when available, the direct, relay, or mixed transport path. Do not require a direct path when a healthy relay path is available.

Expose And Dial Services

Expose exactly one backend per protocol:

fabric expose <protocol> --socket <unix-socket>
fabric expose <protocol> --tcp <host:port>
fabric expose <protocol> --exec [--max-children N] -- <command> [args...]

Use argv after -- for exec exposures; do not pass a shell command string. Exposures persist by default. Add --ephemeral only for a short-lived exposure. Remove a persisted exposure with fabric unexpose <protocol>.

Create a local Unix socket on the dialing machine:

fabric dial <peer> <protocol>

Or create a local TCP listener:

fabric dial <peer> <protocol> --tcp <local-host:port>

Give the printed socket path or TCP address to the consumer. Do not make the consumer import iroh types or implement Fabric's peer checks.

Sync Folders

Use fabric sync to keep a folder converged with trusted peers. Declare sync entries in the authoritative ~/.config/fabric/syncs.toml (a sibling of peers.toml, hand-editable and provisionable); the running daemon watches each folder and syncs changes over the reserved fabric/sync/1 ALPN, gated by the same peer allow-list.

Each [[sync]] entry is {name, folder, peers, policy} plus optional include globs. Use the SAME name on every machine that shares a sync; local folder paths may differ. peers = "*" means every peer in peers.toml. Choose policy = "catalog" (union, newer-wins, never deletes on a peer — a deletion is restored, decommission via an edit) or policy = "bus" (adds tombstone deletes).

fabric sync add <folder> --name <name> --peers "*" --policy catalog
fabric sync ls
fabric sync rm <name-or-folder>
fabric sync reload

fabric sync add writes syncs.toml and reloads; fabric sync reload applies a hand-edited or provisioned file without a restart. Prefer newer-wins on the logical version, not filesystem mtime. A fresh box is declare-then-reload, no interactive step.

Operate The Daemon

Use fabric up for the background daemon and fabric down to stop it. Use fabric up --foreground when another supervisor owns restarts.

Install a native per-user service when persistent OS supervision is wanted:

fabric down
fabric service install
fabric service status

Use fabric service uninstall to remove the service artifact without deleting identity, peer, config, or log data.

Do not migrate a service-manager identity or replace a live managed daemon through that daemon's own fabric shell. Build and verify the replacement, preserve a rollback binary, and use a planned window with an independent recovery path. The service-manager swap restarts Fabric and severs its current remote shell.

Upgrade the binary lockout-safe: install atomically (install.sh uses a temp file plus rename, so it swaps under a running daemon without ETXTBSY) at the exact path the daemon runs from, keep a fabric.rollback copy, then restart through the SUPERVISOR so the restart survives the shell dropping — systemctl --user restart <unit> for a systemd user service, launchctl kickstart -k gui/$UID/<label> for a macOS LaunchAgent, or fabric restart only for a plain fabric up daemon. Never use fabric restart under systemd/launchd (it orphans the daemon from the supervisor), and never a naked fabric down then fabric up over a remote shell (a dropped shell mid-swap is a lockout). Verify from a fresh shell: fabric --version, fabric status, fabric sync ls. See the README "Upgrading Fabric Safely" section for the full procedure.

Keep remote shell disabled unless the user explicitly opts in. Enable it with fabric up --allow-shell or fabric service install --allow-shell. Every trusted peer can obtain a shell while it is enabled. Disable it with fabric restart --no-allow-shell.

Respect State Boundaries

Use ~/.local/share/fabric as the default runtime home and ~/.config/fabric/peers.toml as the default peer file. When --home <dir> or FABRIC_HOME=<dir> is set, keep identity, config, peer, control socket, logs, and command invocations on that same home.

Treat identity.toml as a secret because it contains the persisted private key. Treat peers.toml as the authoritative authorization file and config.toml as daemon policy and exposure configuration. Reject duplicate NodeIDs, duplicate or empty names, and address hints whose ID differs from the peer ID.

Troubleshoot

Check these surfaces in order:

1. Run fabric --version on both machines and align versions.
2. Run fabric peers to validate and inspect the peer file.
3. Run fabric reload-peers after changing that file on a running daemon.
4. Run fabric status to confirm the daemon loaded the expected trust entries and peer reachability.
5. Run fabric ping <peer> before debugging an exposed application protocol.
6. Inspect <home>/logs/daemon.log for a daemon started by fabric up, or <home>/logs/service.out.log and service.err.log for a managed service.
7. Confirm that expose and dial commands use the same protocol string.
8. Run fabric restart after a persistent transport failure; use fabric restart --no-allow-shell when shell must remain disabled.

Use fabric addr and fabric add --addr-json only for deterministic same-machine tests or when an explicit address hint is intentionally required. Normal cross-machine setup should use stable NodeIDs and iroh discovery.

Develop The Repository

Keep the Cargo package and binary name fabric. The repository is https://github.com/compoundingtech/fabric.

Before handing off code changes, run:

cargo fmt --check
cargo check --all-targets
cargo test --all-targets

Also scan owned source, docs, metadata, and help text for stale project names. Do not treat similarly spelled identifiers inside third-party vendored or minified bundles as Fabric branding.