Design a Notification System - Push, Email, and SMS at Billion Scale

Public lesson preview

Design a scalable multi-channel notification system handling push, email, SMS, and in-app notifications with message queues, deduplication, and user preference management.

Learning objectives

By the end of this lesson, you will understand:

• ✓Step 1 - Requirements Gathering
• ✓Step 2 - High-Level Architecture
• ✓Step 3 - Deep Dive: Key Components
• ✓Step 4 - Reliability and Failure Handling
• ✓Step 5 - Third-Party Integration

Lesson outline

1. Step 1 - Requirements Gathering
2. Functional Requirements
3. Non-Functional Requirements
4. Step 2 - High-Level Architecture
5. Core Components
6. Step 3 - Deep Dive: Key Components
7. User Preferences and Opt-Out
8. Priority Queues
9. Step 4 - Reliability and Failure Handling
10. Deduplication
11. Retry with Exponential Backoff
12. Rate Limiting Per User
13. Step 5 - Third-Party Integration
14. Analytics Pipeline
15. Step 6 - Bottlenecks and Optimisations
16. 📚 Further Reading