Design a Logging Service

Last updated: May 12, 2026

Quick Overview

Design a event-driven logging system that handles millions of requests. Discuss trade-offs in consistency, availability, and performance.

Waymo
System Design
Software Engineer
Waymo
May 12, 2026
Software Engineer
Technical Screen
System Design
Medium

37

13

1,468 solved


Design a event-driven logging system that handles millions of requests. Discuss trade-offs in consistency, availability, and performance.

This is a common system design question asked during Technical Screen at Waymo. The interviewer expects you to demonstrate your ability to design large-scale distributed systems, make well-reasoned trade-offs, and communicate your thought process clearly. Waymo values engineers who can think about scalability from day one.

What the Interviewer Expects
  • Systematically gather requirements and estimate capacity (QPS, storage, bandwidth)
  • Design a scalable architecture with clear component responsibilities
  • Make well-reasoned database and caching decisions with trade-off analysis
  • Address consistency vs availability trade-offs specific to the use case
  • Discuss partitioning strategy, replication, and data modeling
  • Cover failure handling, monitoring, and alerting strategies
Key Topics to Cover
Caching strategies (local, distributed, CDN)
High-level architecture and component design
Load balancing and horizontal scaling
Requirements gathering and capacity estimation
Monitoring, logging, and alerting
How to Approach This
  1. Start by clarifying functional and non-functional requirements with the interviewer.
  2. Estimate the scale: QPS, storage, bandwidth. This drives your design decisions.
  3. Draw a high-level architecture first, then deep dive into 1-2 critical components.
  4. Discuss trade-offs explicitly (e.g., consistency vs availability, SQL vs NoSQL).
  5. Address failure scenarios, monitoring, and how the system handles 10x traffic spikes.
Possible Follow-up Questions
  • What happens if one of your database nodes goes down?
  • How would you handle a region-wide outage?
  • How would you implement rate limiting to protect the system?
Practice a Similar Problem on Codemia

Solve a related problem with our interactive workspace, get AI feedback, and view detailed solutions.

Solve on Codemia
Sample Answer
Requirements Clarification

Before diving into the architecture, clarify the scope with the interviewer. For Logging Service, key functional requirements include: what are the co...

Capacity Estimation

Estimate the scale to drive design decisions. Assume 100M DAU with an average of 10 actions per user per day = 1B requests/day ~ 12K QPS average, ~36K...


Submit Your Answer
Markdown supported

Related Questions