If you find yourself adding errors to your code that would have been caught with some basic testing that you usually do (or want to do) but forgot to do or were

If you find yourself adding errors to your code that would have been caught with some basic testing that you usually do (or want to do) but forgot to do or were too lazy to do, then add some tests using whatever the typical framework is for the language you are on. Maybe do some simple github actions CI - it's pretty easy and a decent skill to have regardless. Having "unit" tests is a good habit to get into no matter what, really, but that doesn't mean you need a bit CI/CD pipeline. CD isn't really needed until the creation of your application is complex, or you have actual customers/users that depend on it.