Agreed! Really appreciate the workflow and the fact that it supports Travis' container infrastructure. The speedup on the behat tests alone was impressive nearly half the time.
Just wanted to thank you all as well for your work, very nice tool!
I just opened a PR to integrate it in search_api_solr 8.x-3.x which make the whole travis script much more organized.
Thanks a lot for publishing this code! The more I read through it, the more useful features I find.