How to tackle behavioral interview questions for Staff level at FAANG?

Develop a very strong understanding of what an L6 looks like and work backwards to craft your narrative. Here are some resources to help there:

• To develop an understanding of L6 expectations: [Taro Top 10] Senior Engineer To Staff Engineer (L5 To L6)
• To tackle behavioral interviews well in general: [Taro Top 10] Behavioral Interviews

From an L6, I would expect the following:

• Experience leading multiple teams (at least 2 teams, ideally 3+) with a scope of 15+ engineers
• Track record creating scope out of thin air and convincing many stakeholders (including management up to Director level) to put it on the roadmap
• Long-term vision, operating on the 1 year+ time-scale with huge projects
• Able to solve extremely complex technical problems (more on the infra-side, things that can't be Googled-through at all)

If you don't have any stories that match those criteria, that's perfectly fine as Big Tech L5 still pays extremely well, usually more than Staff at non-Big Tech companies. I really don't recommend making up a story in this case, because if you have never operated equivalent to a Big Tech L6 before, you will likely get PIP-ed immediately if you were to get in as L6 somehow (especially given the current climate).

Here's some more specific resources:

• "Quality to demonstrate for staff MLE during interview?"
• "What is the difference between a Senior and Staff engineer in a System Design Interview?"

This is not about behavioral interviews, but this blog post from Evan King about Staff-level system design interviews has some transferable knowledge: Standing Out in Staff Level System Design Interviews

In particular, the section about "Beauty in Simplicity"