Zuul is a project gating system, which is like a CI/CD system that is primarily focused on ensuring multiple changes are well-tested with each other before being merged.
Zuul was originally written for Gerrit, and as such, has a special relationship with it. Zuul takes advantage of Gerrit topics to support circular dependencies between changes. It may be the only CI system that can do something reasonable with Gerrit submodule subscriptions. And it recently added its eighth method of interfacing with Gerrit.
In addition to all this love for Gerrit, Zuul also seamless integrates with other code review systems allowing teams to use its cross-project dependency features to test changes in Gerrit and GitHub/Gitlab/etc together.
This presentation will provide an overview of Zuul, how it integrates with Gerrit, and recent updates to support new features in Gerrit.