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_examples/basic/6-cqrs-ordered-events/README.md

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+# Example Golang CQRS application - ordered events with Kafka
+
+This application is using [Watermill CQRS](http://watermill.io/docs/cqrs) component.
+
+Detailed documentation for CQRS can be found in Watermill's docs: [http://watermill.io/docs/cqrs#usage](http://watermill.io/docs/cqrs).
+
+This example, uses event groups to keep order for multiple events. You can read more about them in the [Watermill documentation](https://watermill.io/docs/cqrs/).
+We are also using Kafka's partitioning keys to increase processing throughput without losing order of events.
+
+
+## What does this application do?
+
+This application manages an email subscription system where users can:
+
+1. Subscribe to receive emails by providing their email address
+2. Update their email address after subscribing
+3. Unsubscribe from the mailing list
+
+The system maintains:
+- A current list of all active subscribers
+- A timeline of all subscription-related activities
+
+In this example, keeping order of events is crucial.
+If events won't be ordered, and `SubscriberSubscribed` would arrive after `SubscriberUnsubscribed` event,
+the subscriber will be still subscribed.
+
+## Possible improvements
+
+In this example, we are using global `events` and `commands` topics.
+You can consider splitting them into smaller topics, for example, per aggregate type.
+
+Thanks to that, you can scale your application horizontally and increase the throughput and processing less events.
+
+## Running
+
+```bash
+docker-compose up
+```