Design Email Infrastructure for global users

Last updated: October 15, 2025

Quick Overview

Design a high-throughput email system that handles millions of requests. Discuss trade-offs in consistency, availability, and performance.

Oracle
System Design
Software Engineer
Oracle
October 15, 2025
Software Engineer
Onsite
System Design
Medium

7

10

3,935 solved


Design a high-throughput email system that handles millions of requests. Discuss trade-offs in consistency, availability, and performance.

System design interviews at Oracle typically last 45-60 minutes. You are expected to drive the conversation, starting from requirements gathering through to a detailed architecture. The interviewer will evaluate your ability to handle ambiguity and make practical engineering decisions.

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
Database selection and data modeling
Failure handling and fault tolerance
Caching strategies (local, distributed, CDN)
Requirements gathering and capacity estimation
Security and authentication
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
  • How would you handle schema migrations with zero downtime?
  • How would you handle a 10x increase in traffic overnight?
  • What would the deployment pipeline look like for this 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 Email Infrastructure for global users, key functional requirements in...

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