Design Patterns · Senior · Question 55 of 75

How does an "event notification" differ from "event-carried state transfer"?

✓Correct answer: A notification says something happened (consumers query for details); state transfer includes the data so consumers needn't call back
2They're synonyms
3State transfer means sending full database dumps

Explanation

Carrying state reduces coupling at runtime but duplicates data and makes event schemas a contract to version.

Further reading

Martin Fowler: What do you mean by "Event-Driven"? ↗

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