{ pkgs, config, ... }: { services.postfix = { enable = true; enableSubmission = true; domain = config.networking.fqdn; config = { inet_interfaces = "loopback-only"; smtpd_milters = "inet:127.0.0.1:8891"; non_smtpd_milters = "$smtpd_milters"; milter_default_action = "accept"; }; }; services.opendkim = { enable = true; selector = "default"; socket = "inet:8891@127.0.0.1"; domains = "csl:${config.networking.fqdn}"; }; }