That makes more sense, thanks for clarifying. Still, assuming there are no other edge cases there, it doesn't address the other problem where a hypothetical co

That makes more sense, thanks for clarifying. Still, assuming there are no other edge cases there, it doesn't address the other problem where a hypothetical consumer of the output topic is reading an at-least-once feed of your exactly-once topic. In order for that not to be the case then the consumer must also be idempotent, in which case what value was gained from the original deduplication?