Read event/operation identity, generation and sequence; reject duplicates or stale epochs and record local checkpoint/recovery decisions before forwarding eligible work. Local admission does not by itself create a distributed exactly-once guarantee.
Optimized Kafka transactions and application idempotency with the same retry, crash and replay injections and independently recorded external effects.
Fixed-scope diagnostic: €4,500. One approved consumer/stream with a bounded replay and restart trace, one isolated test environment, up to 30 paired repetitions per agreed failure scenario. Competitor and acceptance metrics agreed in writing; unsupported tests marked NOT TESTED.
Included: one 45-minute kickoff, one 45-minute results call, one clarification email thread within five business days; an 8–12-page dossier with method, measured deltas and limitations; aggregate results, SHA-256 manifest, written GO / NO-GO / INCONCLUSIVE.
Payment: 50% on accepted signature and 50% on delivery. Taxes/withholding per quote. Target 10 business days after all complete inputs are accepted. Extra meetings, datasets, environments, tests, external lab costs or engineering require a separately priced signed change order.
Excluded: changes to client code or production, architecture consultancy, on-call/incident handling, certification, guaranteed savings, engine/source licence, and indefinite support. Client owns its data; provider retains proprietary IP. Even NO-GO fulfills a correctly delivered diagnostic. Public terms are not binding before a signed quote and applicable data/privacy terms.