Advanced · 3–4 weeks
Multi-Channel Notification Platform
Unified API to send email, SMS, and push notifications. Template engine, user preferences, delivery status tracking, retry with exponential backoff, and rate limiting per channel.
Why this project
Notification systems appear in every large product. Shows async processing, templating, and delivery guarantees.
Tech stack
Java 17Spring Boot 3KafkaRedisPostgreSQLThymeleaf/MustacheSendGrid/Twilio stubs
Skills demonstrated
- Async processing
- Template rendering
- Retry policies
- User preference management
Interview talking points
- Why Kafka between API and workers
- Template versioning strategy
- Handling provider outage
- Rate limiting to avoid spam flags
Problem statement
Unified API to send email, SMS, and push notifications. Template engine, user preferences, delivery status tracking, retry with exponential backoff, and rate limiting per channel.