Notifications are an important part of the complete end-user experience but can be tricky to get right. Different organizations use different kinds of notifications services such as Slack, OpsGenie, or just good old email. There are dozens of different types of events that may need notification, so it is hard to predict all possible scenarios and optimize for all of them. Finally, every organization has different standards and may want to customize notification in a different way. The Argoproj team has tried several different approaches to notifications during the past year. We’ve received a lot of feedback, learned a lot, and after much experimentation, we are happy to officially announce support for notifications! We’ve prepared a design and implemented a reusable Golang library that accommodates notifications functionality requirements of various Argo projects. The design document and the library defines configuration syntax, base concepts and ensures a consistent user experience in all Argo projects.