The QTE, Cloud Services, and Release Engineering team (collectively known as DevEx, Developer Experience) are kicking off a new project to create an advanced prototype of an on-demand test environment provisioner called Catalyst. This tool is a logical successor to Patch Demo https://patchdemo.wmflabs.org/, which could deploy MediaWikis for testing but not services, and DUCT https://people.wikimedia.org/~kindrobot/duct/presentation.html, which could deploy Mediawikis and services for testing in Wikifunctions http://wikifunctions.org, but was not scalable to other teams/projects.
We expect the MVP (minimum viable prototype) to be ready in approximately two months and would be very interested in input/help from the community, both with the prototype and with where a generally available product might look like thereafter. More information on the project, its technology stack, and how to get involved is at https://wikitech.wikimedia.org/wiki/Catalyst.