Build a real-time Notification Pipeline

Last updated: March 1, 2026

Quick Overview

Design a real-time notification system that handles millions of requests. Discuss trade-offs in consistency, availability, and performance.

Palantir
System Design
Software Engineer
Palantir
March 1, 2026
Software Engineer
System Design Round
System Design
Easy

29

12

1,526 solved


Design a real-time notification system that handles millions of requests. Discuss trade-offs in consistency, availability, and performance.

Palantir asks this during the System Design Round 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
  • Clearly define functional and non-functional requirements
  • Propose a reasonable high-level architecture with core components
  • Choose appropriate data storage solutions with basic justification
  • Discuss basic scaling strategies (horizontal scaling, caching)
  • Identify potential bottlenecks and suggest simple solutions
Key Topics to Cover
Failure handling and fault tolerance
Consistency models and replication
Database selection and data modeling
Message queues and async processing
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 optimize costs as the system scales?
  • What would the deployment pipeline look like for this system?
  • What happens if one of your database nodes goes down?
  • 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

Functional Requirements

  1. Real-time Notifications: The system should deliver notifications in real-time to users based on various triggers, such as data updates or events.
  2. **User Customiza...
Capacity Estimation

Assuming Palantir has around 1 million active users, and each user receives approximately 10 notifications per day:

  • Daily Notifications: 1,000,000 users * 10 notifications = 10,000,000 notifica...

Submit Your Answer
Markdown supported

Related Questions