Pipeline Fan-Out
Splitting independent verification work to run in parallel, bounded by what genuinely has no ordering dependency on anything else.
Most pipeline stages do not depend on each other; they only appear to because they were written as a list. Unit tests, static analysis, dependency scanning, licence checks and container linting all consume the same source and produce independent verdicts, so they can run concurrently and the pipeline waits for the slowest rather than the sum.
The constraint is the join. A fan-out is only safe where every branch consumes the same immutable input and none of them mutate shared state — a shared test database, a fixed port, a common cache key written rather than read. Those constraints are what turn a parallelised pipeline into an intermittently failing one, and they are usually discovered as flakiness rather than diagnosed as a design fault.
Fan-out has a cost ceiling too. Beyond the point where every branch is waiting on a runner, adding parallelism adds queueing, and the observed lead time gets worse while the pipeline diagram looks better.