sithbitd: the mail daemon

Standard port(s): SMTP 2525, submission 2587 (listener disabled by default), IMAP 2143, POP 2110, health 8190.

The combined mail daemon — SMTP MX and submission, IMAP, POP, and the spooler workers (chain pin/send, relay, DSN generation, reconciliation) all in one process. This is the production mail-handling binary; every deployment needs it.

When you need it: always — this is the core of a SithBit deployment. Run exactly one sithbitd per SQLite store (IMAP IDLE push and per-wallet SendMail ordering are in-process); a cloud store (aws/azure) lifts that limit, letting you run one per fleet member — see Scaling out.

Quickstart:

cargo run -p mail-spooler --bin sithbitd

Config file sithbitd.toml, or point SITHBITD_CONFIG at an alternate path.

Note: an empty or missing config runs a loopback dev stack with the chain pipeline disabled — delivered mail stays in state received. This is the expected zero-config shape, not a bug.

See the Configuration reference for the full key/default table.