-case class Trace(msg: String) extends AsyncMessage;
-case class Warning(err: Seq[String]) extends AsyncMessage;
-case class Notify(note: Seq[String]) extends AsyncMessage;
+final case class Trace(msg: String) extends AsyncMessage;
+final case class Warning(err: Seq[String]) extends AsyncMessage;
+final case class Notify(note: Seq[String]) extends AsyncMessage;