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# stateSerialization

The sync engine’s serialized state.

```
var stateSerialization: CKSyncEngine.State.Serialization?
```

## Discussion

This property returns the value you specify for the initializer’s `stateSerialization` parameter.
If you choose to set this property after initialization, assign the state from the most recent [`CKSyncEngine.Event.stateUpdate(_:)`](/documentation/CloudKit/CKSyncEngine-5sie5/Event/stateUpdate(_:)) event handled by your delegate.
However, if this is the first initialization of the associated sync engine, specify `nil` instead.

The default value is `nil`.

---

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