Northrop Grumman Principal Software Engineer interview questions

Applied via employee referral. After ~6 weeks, I received a phone call from a recruiter to set up an interview. The interview was a panel with the hiring manager and a few peers. They all clearly read and understood my resume prior to the interview and we did a deep dive into my previous experiences, what skills they are looking for, and how my skills apply to this role. There were a few behavioral questions. No Leetcode/Hackerrank style live coding questions, which I personally feel are completely unnecessary for this level. Compared to my interview experiences with other companies, this was super low stress and it seemed more like a natural, enjoyable conversation about the job rather than getting endlessly grilled about optimizing big O for code or whatever. This was by far the best interview experience I've had. Less than a week later, I received and accepted an offer.