var people = new List<MyClass>()
            {
                new MyClass{Age = 99,FirstName = "hoge",LastName = "huga",},
                new MyClass{Age = 53,FirstName = "a",LastName = "b",},
                new MyClass{Age = 3,FirstName = "d",LastName = "c",},
            };

            // ok
            IEnumerable<MyClass> listAsEnumerable = (IEnumerable<MyClass>)people;
            var bytes = MessagePack.MessagePackSerializer.Typeless.Serialize(listAsEnumerable);
            var obj = MessagePackSerializer.Typeless.Deserialize(bytes);

            // fails in serialization
            IEnumerable<MyClass> filteredEnumerable = people.Where(f => f.Age > 18);
            bytes = MessagePack.MessagePackSerializer.Typeless.Serialize(filteredEnumerable);
            obj = MessagePackSerializer.Typeless.Deserialize(bytes);

...
    [MessagePackObject]
    public class MyClass
    {
        // Key is serialization index, it is important for versioning.
        [Key(0)]
        public int Age { get; set; }

        [Key(1)]
        public string FirstName { get; set; }

        [Key(2)]
        public string LastName { get; set; }
    }