At my last employer, we were called Systems Engineers. I created tooling to switch us off of a custom packaging solution to using Debian packages. The other part of my project was tooling around Ansible for configuration management across a fleet of over 48,000 vms deployed at over 6,000 locations, with different locations requiring slightly different configurations.

I also helped build a web based system to track approvals and schedules for all the changes.

I think Dev Ops or Systems Engineers would be the most used title for this type of work.