Ask HN: As a female/minority, how do you vet a company before taking a job?

I read stories about what it was like to work at Uber as a woman and I wonder how women and minorities vet a company they are thinking about working for or received a job offer for?

How do you try to screen the environment and figure out if it is a hellscape before you enter?

I'd welcome any feedback. I am working on a research project on how people analyze and screen when offered a new position...