Server configuration management
What do you do, when there are still servers running your containers? Infrastructure as code!
It wasn't enough for me to just work on modernizing how the applications are run and introduce containers, for you see, the containers still run on some sort of a host that has its own configuration, directories, users, permissions services and lots of other things that should also be managed in a sane way.
What I did
To ensure that the developers could see who changed configuration for a particular server, when and also why, I introduced Ansible as a tool for managing it, as well as using the repository as the single source of truth. This allowed for a single configuration mechanism to be applied across multiple nodes. Need a new group or user with certain permissions? Just use the existing template for that and choose which nodes should be affected.
What I learnt
This wasn't one of those large scale deployments that you sometimes hear about, but it was still immensely helpful. Furthermore, this allowed us to run hundreds of administrative tasks every day, to make sure that the state of the server is consistent with what we expected it to be.