Whenever the `createArtifact` end-point is called, the queue will create a record of the artifact and post a message on this exchange.

When a task is successfully completed by a worker a message is posted this exchange.

When a task is created or just defined a message is posted to this exchange.

Whenever Taskcluster fails to run a message is posted to this exchange.

When a task ran, but failed to complete successfully a message is posted to this exchange.

A message is published on task-group-resolved whenever all submitted tasks (whether scheduled or unscheduled) for a given task group have been resolved, regardless of whether they resolved as successful or not.

When a task becomes `pending` a message is posted to this exchange.

Whenever a task is claimed by a worker, a run is started on the worker, and a message is posted on this exchange.