Perhaps it's down to how JIRA is configured. At $JOB, if you mention the JIRA ticket in a commit message, a link will show up in the ticket to show the commit

Perhaps it's down to how JIRA is configured. At $JOB, if you mention the JIRA ticket in a commit message, a link will show up in the ticket to show the commit (it may take some time to show up, but it does eventually). Also, there's an obvious link on the ticket to see all activity.