Ask HN: How would you “try out” companies when internships aren't an option?

I never got the chance to intern as a programmer at big companies, as I never majored in Computer Science. But I'd like to get that experience of getting a feel for their workflow and environment before I really commit to one. Such as, applying for several companies that you have an interest in. But your school years are well behind you, so you can't apply to internships. However, you would want to them out for a few months without needing a long-term commitment, learn the ropes of how they do their work internally. Can you substitute internships with proposing short-term contract work for them, explaining your terms and expectations?