nix3-daemon - Man Page

nix daemon [option…]

• Run the daemon:

# nix daemon

• Run the daemon and listen on standard I/O instead of binding to a UNIX socket:

# nix daemon --stdio

• Run the daemon and force all connections to be trusted:

# nix daemon --force-trusted

• Run the daemon and force all connections to be untrusted:

# nix daemon --force-untrusted

• Run the daemon, listen on standard I/O, and force all connections to use Nix’s default trust:

# nix daemon --stdio --default-trust

This command runs the Nix daemon, which is a required component in multi-user Nix installations. It runs build tasks and other operations on the Nix store on behalf of non-root users. Usually you don’t run the daemon directly; instead it’s managed by a service management framework such as systemd on Linux, or launchctl on Darwin.

Note that this daemon does not fork into the background.

Unless --stdio is used, the daemon listens on a Unix domain socket. The socket path is determined similarly as for the Local Daemon Store:

1. The --socket-path flag, if passed.
2. The NIX_DAEMON_SOCKET_PATH environment variable, if set.
3. Otherwise, daemon-socket/socket within the store’s state directory. The Local Store, Local Daemon Store, and Experimental SSH Store with filesystem mounted each have their own per-store state directory. For other store types, the global NIX_STATE_DIR is used.

nix daemon supports systemd socket-based activation using the nix-daemon.socket unit in the Nix distribution. It supports listening on multiple addresses; for example, the following stanza in nix-daemon.socket makes the daemon listen on two Unix domain sockets:

[Socket]
ListenStream=/nix/var/nix/daemon-socket/socket
ListenStream=/nix/var/nix/daemon-socket/socket-2

• --default-trust

  Use Nix’s default trust.

• --force-trusted

  Force the daemon to trust connecting clients.

• --force-untrusted

  Force the daemon to not trust connecting clients. The connection is processed by the receiving daemon before forwarding commands.

• --process-ops

  Forces the daemon to process received commands itself rather than forwarding the commands straight to the remote store.

      This is useful for the `mounted-ssh://` store where some actions need to be performed on the remote end but as connected user, and not as the user of the underlying daemon on the remote end.

• --socket-path path

  Path to the daemon’s UNIX socket. Overrides NIX_DAEMON_SOCKET_PATH and the default. Incompatible with --stdio.

• --stdio

  Attach to standard I/O, instead of using UNIX socket(s).