How do you handle RabbitMQ message retries and exponential backoff?

Implementing retry with exponential backoff in RabbitMQ uses dead letter queues with TTL. Pattern: 1. Processing queue: normal consumer. On failure (nack with requeue: false), message goes to DLX. 2. Retry queues: create multiple queues with increasing TTLs. retry_30s: {"x-message-ttl": 30000, "x-dead-letter-exchange": "main_exchange"}. retry_60s, retry_300s. After TTL expires, the message is dead-lettered back to the main exchange for reprocessing. 3. Track retry count: use a message header x-retry-count. In the consumer: increment the counter on failure; route to the appropriate retry queue based on count; after max retries, route to the dead letter queue. Libraries: rabbitmq-delayed-message-exchange plugin enables configurable per-message delay without multiple queues. Laravel queues have built-in retry/delay with exponential backoff. Pattern advantages: transient failures (DB connection, API timeout) are automatically retried; permanent failures (invalid data) go to DLQ after max retries.