That time you would have used to test that code in postman, bravely muster the werewithal to write automated tests instead. It's a onetime investment that keeps malfunction in check until code is altered

I acknowledge the fact that it's not always possible. You may have gotten thrown in headfirst into unfamiliar territory ie tech stack, or inherit a monolith where no tests were pioneered. Or you may be strongly constrained for time. But in events that you can, it's worthwhile

Whether automated or manual, Testing your work the least professional thing to do before handover. Might as well swallow the bitter pill of avoiding the gui shortcut, and write those certifications once and get it over with

My preference is to write a boilerplate that gets generated each time I create a new module/resource management classes. Another strategy is to write them immediately after completing implementation of each endpoint/user story/feature, even if they're not run immediately. That way, they don't pile up in the end

Or you could try the tdd that everyone else cherishes. Whatever works for you, the end justifies the means