Module worker 

Async delivery worker that drains the queue + dispatches via SMTP (feature-gated). Background delivery worker: polls the outbound queue, signs, and delivers to remote MX hosts.

Sub-modules:

• [delivery] — per-domain orchestration (MX resolve, retry/bounce, DSN enqueue).
• [smtp] — per-MX SMTP delivery with STARTTLS / DANE policy handling. [TlsPolicy] is re-exported from here.

Structs

DeliveryWorker

background delivery worker that polls the queue and delivers messages

WorkerConfig

Delivery worker configuration.

Enums

TlsPolicy

TLS policy for outbound connections

Functions

deliver_domain_static

deliver messages to a single domain (used by concurrent workers)

group_by_domain

group queued messages by target domain for efficient delivery

try_deliver_via_mx

try to deliver messages via a specific MX host

try_deliver_via_mx_with_tls

Try to deliver messages via a specific MX host with explicit TLS policy and optional ClientConfig override.