It’s unbelievable right? I’m flabbergasted that there are engineers like this shipping code.
The answer: you don't!
Seems like this reality will become increasingly justified and embraced in the months to come. Really though it feels like a natural progression of the package manager driven "dependency hell" style of development, except now it's your literal business logic that's essentially a dependency that has never been reviewed.
My process is probably more robust than simply reviewing each line of code. But hey, I am not against doing it, if that is your policy. I had worked the old-fashioned way for over 15 years, I know exactly what pitfalls to watch out for.