The Lift skin is an example of how to take advantage of the SkinMustache class in your mediawiki instance.
See https://www.mediawiki.org/wiki/Skin:Lift
See also the Development guide that explains how this skin was made using MediaWiki's SkinMustache class: https://www.mediawiki.org/wiki/Skin:Lift/Development_guide
Automatically works with Users Online extension: https://github.com/LorenMaxwell/mediawiki-extensions-usersonline