self: {
  name = "matrix-ops-bot-nixos-module";

  nodes.machine =
    { pkgs, ... }:
    {
      imports = [ self.nixosModules.default ];

      environment.systemPackages = [ pkgs.curl ];

      environment.etc."matrix-ops-bot/config.json".text = builtins.toJSON {
        routing_keys = [ ];
        log_level = "INFO";
        matrix = {
          homeserver = "http://127.0.0.1:9";
          user_id = "@ops-bot:example.invalid";
          password = "not-a-real-password";
          device_name = "nixos-test";
          store_path = "/var/lib/matrix-ops-bot/matrix";
          verify_ssl = false;
        };
      };

      environment.etc."matrix-ops-bot/bot.env".text = ''
        BOT_LOG_LEVEL=DEBUG
      '';

      services.matrix-ops-bot = {
        enable = true;
        port = 1111;
        configFile = "/etc/matrix-ops-bot/config.json";
        envFile = "/etc/matrix-ops-bot/bot.env";
      };
    };

  testScript = ''
    machine.wait_for_unit("multi-user.target")
    machine.wait_for_unit("matrix-ops-bot.service")
    machine.wait_for_open_port(1111)

    unit = machine.succeed("systemctl cat matrix-ops-bot.service")
    assert "DynamicUser=true" in unit, unit
    assert "StateDirectory=matrix-ops-bot" in unit, unit
    assert "LoadCredential=config.json:/etc/matrix-ops-bot/config.json" in unit, unit
    assert "LoadCredential=bot.env:/etc/matrix-ops-bot/bot.env" in unit, unit

    machine.succeed("test -f /run/credentials/matrix-ops-bot.service/config.json")
    machine.succeed("test -f /run/credentials/matrix-ops-bot.service/bot.env")

    machine.succeed("curl -sf http://127.0.0.1:1111/ | grep -F '\"message\":\"Hello World\"'")
  '';
}