SerializationProxy

final class SerializationProxy[A](var coll: LazyList[A]) extends Serializable

This serialization proxy is used for LazyLists which start with a sequence of evaluated cons cells. The forced sequence is serialized in a compact, sequential format, followed by the unevaluated tail, which uses standard Java serialization to store the complete structure of unevaluated thunks. This allows the serialization of long evaluated lazy lists without exhausting the stack through recursive serialization of cons cells.

Source:
LazyList.scala
class Object
trait Matchable
class Any