The Idempotency Patterns I Actually Use in Production (Not the Blog Version)

This is the paid deep-dive. The free Medium version told the story. This one tells you exactly what I build, why each decision is the way it is, and the three places I have personally gotten this wron

If you read the public version, you have the narrative: at-least-once delivery is a literal statement, a consumer that is not idempotent will double-process under deploy and network pressure, and the symptom shows up weeks later in a place that has no stack trace.

That is the part everyone can write. Here is the part that took me actual incidents to learn, and that I have never seen written down honestly in one place.

medium blog link here.

If you want all of this as a working reference the schema, the transaction-boundary decision tree, the redelivery alerting config, the reconciliation playbook, and the four other silent-corruption patterns I did not have room for here (poison messages, ordering assumptions, the DLQ that quietly fills, partial-batch acks) it is collected and kept current here

Why the naive idempotency check is a different bug, not a fix