I quit my last job due to a situation like this. The person that built the entire application was very weak technically. I'm pretty sure the motivation for bri

I quit my last job due to a situation like this. The person that built the entire application was very weak technically. I'm pretty sure the motivation for bringing me in was that I would "fix up" the entire mess. There was no documentation, no tests, and tons of code copy/pasted everywhere. I spent a year trying to improve it, but for every thing I'd clean up, the original engineer would write twice as much new code without consulting me. I tried to get them to do architecture reviews and code reviews, but everything was always an emergency that needed to go live immediately. If I ever thought about joining a startup that small again, I'd make sure I got to look at a representative chunk of their code base first. And if it looked like it needed a lot of work, I'd grill the existing engineers hard to make sure I can actually do what they want me to do.