zuul/tests/fixtures/layouts/supercedent.yaml

- pipeline:
    name: post
    manager: supercedent
    trigger:
      gerrit:
        - event: ref-updated
          ref: ^(?!refs/).*$

- job:
    name: base
    parent: null
    run: playbooks/base.yaml

- job:
    name: post-job

- project:
    name: org/project
    post:
      jobs:
        - post-job