The Wikimedia movement lacks a formal governance structure for organized groups focused on exploring and resolving shared technical concerns. Many of our on-wiki communities have groups known as WikiProjects which fill a similar role in the content creation and curation spaces of the movement. In some communities outside of the Wikimedia movement a Special Interest Group (SIG) fills this role. Per the enwiki article:
A Special Interest Group (SIG) is a community within a larger organization with a shared interest in advancing a specific area of knowledge, learning or technology where members cooperate to affect or to produce solutions within their particular field, and may communicate, meet, and organize conferences.
The absence of a structure for organizing such groups leaves any interested parties to create their own ad hoc structures. Few examples of such groups other than the Architecture committee and the closely related Front-end standards group can be found which have survived over the long term. Both of these groups are strongly supported by Wikimedia Foundation technical managers which may have some degree of correlation with their success. Both groups have also been granted some degree of ownership and authority in their respective areas of interest. Without a governance framework it is unclear how another group interested in promoting and improving a topic like technical documentation or testing practices would be granted such authority.
TODO: research SIG governance models in other organizations and propose either wholesale adoption of one of them or construct a hybrid that fills the needs of the Wikimedia technical community.