table.chain local_rewrites {
    optional_step regexp "(.+)\+(.+)@(.+)" "$1@$3"
    optional_step static {
        entry postmaster postmaster@$(primary_domain)
    }
    optional_step file $(alias_file)
}

msgpipeline local_routing {
    # Insert handling for special-purpose local domains here.
    # e.g.
    # destination lists.example.org {
    #     deliver_to lmtp tcp://127.0.0.1:8024
    # }

    destination postmaster $(local_domains) {
        modify {
            replace_rcpt &local_rewrites
        }

        deliver_to &local_mailboxes
    }

    default_destination {
        reject 550 5.1.1 "User doesn't exist"
    }
}

smtp tcp://0.0.0.0:25 {
    limits {
        # Up to 20 msgs/sec across max. 10 SMTP connections.
        all rate 20 1s
        all concurrency 10
    }

    dmarc yes
    check {
        require_mx_record
        dkim
        spf
    }

    source $(local_domains) {
        reject 501 5.1.8 "Use Submission for outgoing SMTP"
    }
    default_source {
        destination postmaster $(local_domains) {
            deliver_to &local_routing
        }
        default_destination {
            reject 550 5.1.1 "User doesn't exist"
        }
    }
}


# Outgoing email

submission tls://0.0.0.0:465 tcp://0.0.0.0:587 {
    limits {
        # Up to 50 msgs/sec across any amount of SMTP connections.
        all rate 50 1s
    }

    auth &local_authdb

    source $(local_domains) {
        check {
            authorize_sender {
                prepare_email &local_rewrites
                user_to_email identity
            }
        }

        destination postmaster $(local_domains) {
            deliver_to &local_routing
        }
        default_destination {
            modify {
                dkim $(primary_domain) $(local_domains) default
            }
            deliver_to &remote_queue
        }
    }
    default_source {
        reject 501 5.1.8 "Non-local sender domain"
    }
}

target.remote outbound_delivery {
    limits {
        # Up to 20 msgs/sec across max. 10 SMTP connections
        # for each recipient domain.
        destination rate 20 1s
        destination concurrency 10
    }
    mx_auth {
        dane
        mtasts {
            cache fs
            fs_dir mtasts_cache/
        }
        local_policy {
            min_tls_level encrypted
            min_mx_level none
        }
    }
}

target.queue remote_queue {
    target &outbound_delivery

    autogenerated_msg_domain $(primary_domain)
    bounce {
        destination postmaster $(local_domains) {
            deliver_to &local_routing
        }
        default_destination {
            reject 550 5.0.0 "Refusing to send DSNs to non-local addresses"
        }
    }
}
