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Model Evolution and Compatibility
Because Message and Entities are serialized and deserialized, it is important that modeled objects can evolve over time without breaking the ability to deserialize objects from a previous evolution of a model. For example, if the type of a message field is changed from one release of your application to the next, a receiver that is still on an older version that receives the message won't be able to deserialize the message. To ensure that such issues don't occur, follow the set of guidelines and rules outlined below. Similarly, if your application is configured to persist to a transaction log and you later try to read from the transaction log with the newly generated code, it won't be able to read from the older serialization.
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