{inputs, ...}: {
  flake.nixngConfigurations.dovecot = inputs.nixng.nglib.makeSystem {
    system = "x86_64-linux";
    name = "ra-systems-dovecot";
    inherit (inputs) nixpkgs;
    config = {pkgs, ...}: {
      config = {
        dumb-init = {
          enable = true;
          type.services = {};
        };

        services.dovecot = {
          enable = true;
          package = pkgs.dovecot;
          config = {
            protocols = "imap lmtp";

            # auth
            ssl = "no";
            disable_plaintext_auth = "no";
            auth_mechanisms = "plain login";

            mail_location = "maildir:/maildir/%u";

            protocol."imap" = {};
            protocol."lmtp" = {
              mail_plugins = ["sieve"];
            };

            plugin."" = {
              sieve = "/mail-configuration/entry.sieve";
            };

            mail_plugin_dir = pkgs.symlinkJoin {
              name = "dovecot-modules";
              paths = map (pkg: "${pkg}/lib/dovecot") [pkgs.dovecot pkgs.dovecot_pigeonhole];
            };

            # Optimizations:
            # dotlock_use_excl = true;
            maildir_copy_with_hardlinks = true;

            lda_mailbox_autocreate = "yes";
            lmtp_save_to_detail_mailbox = "yes";
            service."lmtp" = {
              inet_listener."lmtp" = {
                address = ["127.0.0.1"];
                port = 24;
              };
            };

            service."imap-login" = {
              inet_listener."imap" = {
                port = 143;
              };

              # inet_listener."imaps" = {
              #   port = 993;
              #   ssl = "yes";
              # };
            };

            # Authentication configuration:
            auth_debug = true;
            log_path = "/proc/self/fd/1";
            info_log_path = "/proc/self/fd/1";
            debug_log_path = "/proc/self/fd/1";

            passdb."" = {
              driver = "passwd-file";
              args = "scheme=plain username_format=%u /secrets/passwd.dovecot";
            };
            userdb."" = {
              driver = "passwd-file";
              args = "username_format=%u /secrets/passwd.dovecot";
              default_fields = "uid=vmail gid=vmail home=/maildir/%u";
            };
          };
        };
      };
    };
  };
}