Sometimes it doesn't matter how hard you work, your going to get laid off either way.
Just showing up can sometimes make the difference.
Your not paid to be a software developer. Your being paid to be a problem solver.
That's a great question and there are so many good answers in this thread.
Don't expect your superiors to ever back you up. I got burned so many times. I knew I was right, but they didn't have a backbone and only thought about the budget, their reputation, and the work they'd have to put in for damage control. I wanted to shut restaurants for their filthiness, but "Oh noes, what will the community think". Well, if someone dies, then it's on your head. DOCUMENT EVERYTHING.
Even if a conversation or direction was made verbally, always follow up with an email to say "Just to confirm our conversation today, you have directed me to...." Even if it's about holidays. My old boss was such a prick. Him and all upper management are the reason I am suspicious of everyone and everything.