Quality to demonstrate for staff MLE during interview?

When it comes to Big Tech companies, the signal for leveling (especially at L5 and beyond) primarily comes from the behavioral and system design rounds. For the LeetCode rounds, engineers can show more senior signals (edge case coverage, more detailed thoughts on run-time/space analysis, and extension ideas), but they're mainly judged pass/no pass.

The tricky thing about L6+ is that every staff engineer is very different, and I imagine this would apply to MLE as well. Because of this, the signals I'll share are more high-level.

Behavioral

For these interviews, I would look for the following from a staff engineer:

• Have they led projects across multiple teams?
• Can they clearly describe strategies they used to align very XFN stakeholders? (i.e. engineers in very distant orgs or non-eng stakeholders)
• Were they able to come up with multiplicative, long-lasting solutions to problems?
• Do they have a history of empowering other engineers and raising them quickly?
• Is there a track record of creating scope and coming up with innovative approaches that their team would have otherwise missed?

Tactically, my advice for you and anyone else interviewing for a senior/staff role is to prepare a strong narrative before the interview (put it in a Google Doc/Notion). You are almost certainly going to be asked to describe the project you're the most proud of - Make sure that you have something ready that shows as many advanced engineering signals as possible.

Here's some good case studies to help you grok what staff-level behavior looks like - If your story shares similar threads to these, you're in good shape:

• [Case Study] Building A Meta Internal Tool To Empower An Entire Org: Staff Promotion Story
• [Case Study] Revamping Oncall For 20 Instagram Engineers - Senior to Staff Project
• [Case Study] Building XFN Alignment Across Multiple Orgs (w/ Staff Engineer Cat Chen)

System Design

It depends a lot on the problem, but here's some ideas:

• How far ahead is the technical design looking? Staff engineers will generally look 1-2 years into the future.
• How thorough is it when it comes to handling edge cases across robustness, reliability, security, and other system design angles? A staff engineer should be able to go into the weeds for any of these.
• Can the engineer come up with a compelling case for the product roadmap and design the system accordingly so it scales up properly over time?
• Is there a plan to vet the quality of the system on top of the raw technical design? What kind of logging and monitoring would be built on top of it?

Lastly, here's another good discussion on L5 vs. L6 expectations when it comes to interviewing: "How to distinguish between the performance of a strong L5 (senior) vs. an L6 (staff) interview performance?"