How does Rails handle large-scale idempotency in distributed systems?

Rails implements idempotency using unique request keys, database constraints, and deduplication stores.

Idempotency ensures that repeated execution of the same operation produces the same result. In Rails APIs, this is commonly implemented using idempotency keys stored in Redis or persistent DB tables. For distributed jobs, idempotency prevents duplicate side effects such as double charging or duplicate record creation. This is critical for retries, webhook processing, and network failure recovery.