Serialization is disclosed. It is detected if a component included in a graph of components associated with a user session on a first system has not changed since a prior serialization to a second system. A token is sent to the second system during a current serialization, instead of the component, indicating the component has not changed since the prior serialization. De-serialization is disclosed. a token is received at a first system from a second system, in a stream of serialized data from the second system, that indicates that a component on the second system has not changed since a prior serialization. A cached version of the component is retrieved. The cached copy is used to reconstruct on the second system a state of a user session with which the component is associated on the second system.