Two of your saved sources point the same way: budget retries by idempotency key, not by worker. Stripe assigns each key a retry budget, which drops duplicate side-effects to near-zero during regional failover1. Your Kafka note reaches a similar conclusion via exactly-once delivery2.
sources
1
Stripe rebuilt its retry engine around idempotency budgets
techcrunch · saved may 21
2
Kafka exactly-once, revisited
confluent · saved apr 14
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