mail notifications are nice but usually usually someone creates a rule for them and never looks at them again. Plus notifications because of failure are usually not reliable, since the same failure that made the job crash may lead to the notification not being sent.
Instead I am using https://healthchecks.io/ and just notify their api at the end of a job. If such a notification is missing for a configured time interval their service can send me various notifications (mail, push notifications, chat messages, sms, …).