This module has been used in multiple trainings by Netways GmbH. Structured as a step by step hands-on workshop it wants to get you started with writing Icinga Web 2 modules. The latest version is hosted at git.netways.org.
As of this writing there is only a German version available: Icinga Web 2 erweitern. Nobody wrote an English translation yet. So if you want to help us with this task please let us know. We'd love to publish this in an English version on icinga.org.