Engineering Manager · Virtual Onsite · System Design

Google — Engineering Manager ✅ Passed

Level: Staff-Level

Round: Virtual Onsite · Type: System Design · Difficulty: 8/10 · Duration: 60 min · Interviewer: Unfriendly

Topics: System Design, Authentication, Data Storage, Google Maps, Image Processing

Location: Mountain View, CA

Interview date: 2026-01-15

Summary

I had a system design interview focused on designing a system for Google Maps Street View storage.

Details

The system design interview involved designing a system to support Google Maps Street View storage, where images are uploaded from taxis equipped with cameras. These images would be processed downstream for image understanding, user display, and map generation.

The interviewer, an engineer, listened attentively and asked questions throughout the session. The entire hour was structured as an open-ended Q&A, with the flow driven by me. The interviewer primarily interrupted to ask questions at critical points, requiring strong systematic expression and on-the-spot judgment.

My approach was to begin with requirements gathering, focusing on core system needs, user and request volumes, and other requirements such as latency and stability. I provided a high-level design initially to gather feedback before delving into details. During the process, I was frequently asked why certain design choices were made and the tradeoffs involved, such as the specific storage solutions. I was also asked about additional features I would add given more time, emphasizing the importance of thoroughly understanding each component, including its pros and cons and how it compares to similar components.

Other questions included:

• How to design authentication to ensure security and handle compromised tokens.
• How to design upload request responses and handle network issues during uploads.

Preparation Tips & Key Takeaways

What I Learned

• Starting with requirements gathering is crucial to ensure a clear understanding of the system's core needs and constraints.
• Presenting a high-level design first allows for early feedback and adjustments before diving into detailed implementations.
• Thoroughly understanding the trade-offs of different design choices and components is essential for making informed decisions.

Recommended Preparation

System Design

• Study common system design patterns for handling large-scale data storage and processing.
• Review authentication and authorization mechanisms for securing data and APIs.

Data Storage

• Familiarize yourself with different storage solutions and their trade-offs, such as object storage, distributed file systems, and databases.
• Understand the scalability and performance characteristics of various storage options.

Networking

• Study techniques for handling network issues during data uploads, such as retry mechanisms and error handling.
• Review the design of APIs for efficient data transfer and communication between components.