Not specifically for programmers per-se, but the book "The First 90 Days" by Michael Watkins from Harvard Business Review was very valuable for me when switchin

Not specifically for programmers per-se, but the book "The First 90 Days" by Michael Watkins from Harvard Business Review was very valuable for me when switching to a new company when I was still in the corporate world. It's targeted at managers, but I find the situations translate to nearly anyone. It talks about making the right connections, working with your new boss, and so forth. Your first 90 days leave a lasting impression on your co-workers and manager, so it may be worth perusing.