DbActor

public class DbActor : ReceiveActor
    {
        public class Query
        {
            public Func<Db, IQueryable> Filter;
        }

        public DbActor()
        {
            Receive<Query>(query =>
            {
                using (Db db = new Db())
                {
                    var filter = query.Filter(db).ToListAsync().Result;
                    Sender.Tell(filter);
                }
            });
        }
    }