ZScaler Senior Staff SDE - Selected - Feb 26
Summary
I interviewed for a Senior Staff SDE at ZScaler, cleared multiple rounds including a coding rate‑limiting task, a system‑design discussion, and a technical‑managerial interview, and received an offer.
Full Experience
Stage 1: With a developer. Multiple questions about my projects, approaches handled for around 40 minutes. Then, next 45 minutes I was asked to code rate limiting, and it should handle criteria like job effort, user limit, per day limit, per hour limit. Stage 2: With a senior developer, questions about the project. System design: Design a large‑scale metrics monitoring and alerting system for a global microservices architecture. The system should allow engineers to track service health, visualize performance via dashboards, and receive real‑time alerts when anomalies occur. And we need to design it for a large‑scale system design problem. Final: Techno managerial: Multiple questions about projects. Questions on remote browser isolation, zero trust mechanism, difference between vpn and rbi, mechanisms to respond with blob data to users efficiently/securely, peer to peer downloads, chunking, streaming, session timeout vs request timeout, how do you make a video playable after partial downloads, etc.
Interview Questions (3)
Implement Rate Limiting with Multiple Criteria
Implement a rate limiting feature that enforces several constraints simultaneously: limit per job effort, limit per user, limit per day, and limit per hour. The solution should correctly track usage across these dimensions and reject requests that exceed any of the specified limits.
Design a Large‑Scale Metrics Monitoring and Alerting System
Design a large‑scale metrics monitoring and alerting system for a global microservices architecture. The system must allow engineers to track service health, visualize performance via dashboards, and receive real‑time alerts when anomalies occur. Consider scalability, fault tolerance, data ingestion, storage, querying, and alert routing in your design.
Enable Video Playback after Partial Download
Explain how to make a video playable after a partial download. Discuss techniques for streaming, chunking, handling range requests, and ensuring secure and efficient delivery of video content to the client.