At a previous job we used it to test our ansible playbooks via molecule, which were part of a CI/CD pipeline to create AWS AMIs.

It worked well and was nicer to deal with than test kitchen for testing UNIXy things (is service running and/or enabled, does file have right permissions, does file include $TEXT, etc). It was very useful for us during big linux upgrades, such as when ubuntu went from upstart to systemd. It can also be good at capturing edge cases with brittle outcomes (especially as ansible went through enormous changes after the red hat acquisition).

Dislikes? I had to fight with pyenvs a bit..

On my homelab. It really feels like a dream come true for my usecase. No more puppet agents. No more declarative syntax, that you have to work around to do basic imperative ways. Or use a module, that stopped being maintained 3 years ago. Just plop a file here and there through ssh.

I tried something like that, using PyInfra to setup VMs for agent. But gave up, too much complexity for too little gain. Just ask the agent to create a small install script.