CI is different from the others, here! At minimum, building a "happy path(s)" test harness that can run with replicable results, and will run on every one of yo

CI is different from the others, here! At minimum, building a "happy path(s)" test harness that can run with replicable results, and will run on every one of your commits, is a first step, and also helps to understand the codebase. And you're jumping around - and you'll have to! - odds are you'll have a bunch of things changed locally, and might accidentally create a commit that doesn't separate out one concern from another. CI will be a godsend at that point.