Daemon mode

Background instances

--daemon starts servd in the background under a supervisor that keeps a worker alive. Daemons are scoped per user and per port.

servd --static=./dist --port=8080 --daemon

--daemon returns only after the worker is actually listening, so it is safe to script:

servd 0.1.0 http daemon started on 0.0.0.0:8080 (supervisor pid 41233, worker pid 41240)
log: /Users/you/Library/Caches/servd/8080/servd.log

Inspect and stop

servd --status --port=8080
servd --stop   --port=8080

• --status prints the state (running, restarting, or failed), the supervisor/worker PIDs, the restart count, and the log path. It exits non-zero when not running, so it works in scripts.
• --stop terminates the instance; stopping an absent daemon succeeds quietly.
• --status and --stop accept only --port.

Restart policy

• A crashed worker restarts with exponential backoff, up to five consecutive times.
• A worker that stays up resets the restart budget.
• Once the budget is exhausted the instance is marked failed and holds until you --stop it, then start again.

servd :8080 restarting (restart 2/5, next in 2000ms, last exit: exit status 1)

Logs

Supervisor and worker output is written to a per-port log file whose path is printed by --daemon and --status. Logs rotate at 5 MiB with one backup (servd.log and servd.log.1).

How it works

servd copies its own binary into a private, per-user instance directory, then spawns a detached supervisor. The supervisor holds an instance lock, exposes an authenticated loopback control endpoint (used by --status/--stop), and manages the worker lifecycle. Internal handshakes are token-authenticated over loopback only.

A typical flow

# start a preview that survives crashes and logouts of the controlling shell
servd --spa=./frontend --proxy=/api/=http://localhost:9000/api/ --port=8080 --daemon

# check on it later
servd --status --port=8080

# stop when done
servd --stop --port=8080

Only one daemon can hold a port at a time; starting a second one for the same port reports that a daemon already exists.