System designHardsd-g051

Subject Edge computeLevel Senior–Staff~45 minCommon in Security interviewsIndustries Technology, Software development

Question

Design an edge-compute platform feature: run customer JWT validation and A/B-bucketing logic at 300 POPs so requests get authenticated and routed without a round trip to a central region. Constraints: bucketing must be deterministic per user globally, JWT revocation must take effect within ~30s, and you can't ship secrets to untrusted POPs in plaintext. Explain where state and secrets live and how you keep edge logic consistent worldwide.

What a strong answer looks like

Clarify scale and constraints first. Propose a clean component breakdown, then go deep on the hard parts — data model, bottlenecks, consistency, failure modes — and name the trade-offs you are making.

Learn the concepts

Narrate your design

Loading whiteboard…

Run or narrate your approach, then ask the coach.