Build a scalable Email Pipeline
Last updated: July 20, 2025
Quick Overview
Design a scalable email system that handles millions of requests. Discuss trade-offs in consistency, availability, and performance.
Optiver
July 20, 202547
14
63 solved
Design a scalable email system that handles millions of requests. Discuss trade-offs in consistency, availability, and performance.
This is a common system design question asked during System Design Round at Optiver. 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. Optiver 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
How to Approach This
- Start by clarifying functional and non-functional requirements with the interviewer.
- Estimate the scale: QPS, storage, bandwidth. This drives your design decisions.
- Draw a high-level architecture first, then deep dive into 1-2 critical components.
- Discuss trade-offs explicitly (e.g., consistency vs availability, SQL vs NoSQL).
- Address failure scenarios, monitoring, and how the system handles 10x traffic spikes.
Possible Follow-up Questions
- How would you handle a 10x increase in traffic overnight?
- How would you migrate from a monolithic to a microservices architecture?
- What happens if one of your database nodes goes down?
Practice a Similar Problem on Codemia
Solve a related problem with our interactive workspace, get AI feedback, and view detailed solutions.
Solve on CodemiaSample Answer
Requirements
- Functional Requirements:
- Handle millions of incoming email requests per day.
- Support multiple email formats (HTML, plain text, attachments).
- Allow for API-based email triggering and ...
Capacity Estimation
-
Estimation of Requests:
- Assume 10 million emails sent per day.
- This translates to approximately 115 emails per second (QPS).
-
Storage Requirements:
- Assuming an average email si...
Submit Your Answer
