Design Notification Infrastructure for microservices
Last updated: August 28, 2025
Quick Overview
Design a event-driven notification system that handles millions of requests. Discuss trade-offs in consistency, availability, and performance.
SentinelOne
August 28, 2025146
12
4,233 solved
Design a event-driven notification system that handles millions of requests. Discuss trade-offs in consistency, availability, and performance.
SentinelOne asks this during the Technical Screen to assess your architectural thinking. They want to see how you decompose a complex problem, choose appropriate technologies, and reason about failure modes. Strong candidates proactively discuss monitoring, alerting, and operational concerns.
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 optimize costs as the system scales?
- How would you handle a 10x increase in traffic overnight?
- 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
- Event Ingestion: Ability to receive notifications from multiple microservices asynchronously.
- Event Processing: Process notifications in real-time and support...
Capacity Estimation
Assuming SentinelOne has around 1 million active users with an average of 10 notifications per user each day:
- Total Notifications per Day: 1,000,000 users * 10 notifications/user = 10,000,000 no...
Submit Your Answer
