About this app

At-least-once delivery means duplicates are normal traffic, not an incident. Generates a delivery tape with a chosen duplicate and out-of-order rate, then runs it through no dedupe, an idempotency key with a TTL, a content hash, or per-entity sequence numbers. Shows where each one fails: a TTL shorter than the provider retry schedule, a hash that cannot tell a retry from a genuine repeat charge, and sequence numbers that silently discard events which merely arrived late.