Firefox-CI & Taskcluster

Taskcluster is Mozilla’s home grown task execution framework and CI service. Mozilla runs two instances of Taskcluster; Community and Firefox-CI.

The community instance is operated by the Taskcluster team. It acts as a reference instance and primarily provides CI for projects that are adjacent to, but not strictly owned by MoCo.

The firefox-ci instance is operated by Release Engineering. It provides CI for most MoCo products (including Firefox) and supporting repos.

This section goes into some detail on core Taskcluster concepts, as well as Firefox-CI specific extensions that underpin Mozilla’s CI.

• How Tasks are Triggered
  • [Pulse ->] hooks -> build-decision
  • Through action hooks
  • Through taskcluster-github
  • Side note: taskcluster_yml_repo
• Scopes
  • Ci-configuration
  • Roles
  • Expansion of scopes in Automation
  • Conventions
  • Docker- and Generic-Worker scopes
  • Scriptworker scopes
• Rerun vs Retrigger
  • Intermittent tests in treeherder: retrigger
  • Broken Pull Request tasks: rerun
  • Broken release tasks: rerun
  • Testing scriptworker pools outside of the release: retrigger (force)
  • Notarization poller timeouts: rerun (force)
  • Release tasks with broken dependencies: cancel + rerun
  • Deadline-exceeded leaf node release tasks