Rework Loop
The cyclical structure introduced when a verifier rejects a producer's output and the producer must retry. Each pass through the pipeline is still a DAG; the cyclicality lives in the attempt-counter, not in any single pass. Expected total work scales as 1/accept producer-runs under unbounded retries.
Why It Exists
Conflating "the pipeline has a cycle" with "the pipeline is not a DAG" makes the math intractable. The right framing: every individual pass is a DAG, and the rework loop is a Markov chain over attempts. This keeps topological order, parallelism, and associative composition intact.
Related Terms
Verifier-Producer - A two-node topology where a producer P emits a candidate and a verifier V either accepts it (forwards to output) or rejects it (loops back to P for a rerun).
Partial Rework - A pipeline design where the producer emits N independent parts and the verifier checks each part independently.