# Architecture principles whose scope is messaging

> 7 records

This index as JSON: https://banes-lab.com/json/api/facets/architecture/scope/messaging

## Entries

- [Message Broker](https://banes-lab.com/records/architecture/message-broker.md): Descriptive data about topics, queues and routing rules, held by an intermediary service that delivers messages between producers and consumers.
- [Integration Events](https://banes-lab.com/records/architecture/integration-events.md): A design pattern that publishes a versioned public event, mapped from an internal domain event, for consumers outside the service.
- [Outbox Pattern](https://banes-lab.com/records/architecture/outbox-pattern.md): A design pattern that writes an outgoing message in the same local transaction as the state change, and a relay publishes it afterwards.
- [Dead-Letter Queue](https://banes-lab.com/records/architecture/dead-letter-queue.md): A design pattern that moves a message which keeps failing into a separate queue, where it can be inspected and reprocessed.
- [Idempotent Consumer](https://banes-lab.com/records/architecture/idempotent-consumer.md): A design pattern in which a consumer records each message it has processed, so a redelivered message has no second effect.
- [Competing Consumers](https://banes-lab.com/records/architecture/competing-consumers.md): A design pattern in which several consumers read from one queue, and each message goes to only one of them.
- [Sharding](https://banes-lab.com/records/architecture/sharding.md): A design pattern that splits a dataset across separate stores by a shard key, and routes each request to the shard that holds its key.