I have worked on a large PHP monolith with 100+ devs. We rarely had any major bugs make it to production. I think unit tests really helped there. Of course, hav

I have worked on a large PHP monolith with 100+ devs. We rarely had any major bugs make it to production. I think unit tests really helped there. Of course, having QA department helped a lot too but unit tests are first line of defense. And we also used all other best practices such as PSR code formatting standards, linters, code reviews, etc.