P : Plugin.S
type t
val start : config:Config.t ‑> log:Async_smtp__.Mail_log.t ‑> t Async.Deferred.Or_error.t
val config : t ‑> Config.t
val ports : t ‑> int list
val close : ?timeout:unit Async.Deferred.t ‑> t ‑> unit Async.Deferred.Or_error.t