_: {
    services.stalwart-mail = {
        enable = true;
        settings = {
            server = {
                hostname = "mail.jacekpoz.pl";
                run-as = {
                    user = "stalwart";
                    group = "stalwart";
                };
                listener = {
                    smtp = {
                        bind = [ "0.0.0.0:9900" ];
                    };
                };
            };
            global = {
                thread-pool = 4;
                shared-map = {
                    shard = 32;
                    capacity = 10;
                };
                tracing = {
                    method = "journal";
                    level = "warn";
                };
            };
        };
    };
}