Distributed Notification Service for Multi-Channel Messaging

For a multi-tenant platform requiring reliable, scalable messaging, I architected a distributed notification service capable of handling email, SMS, and in-app alerts with strict delivery guarantees and multi-channel coordination.

The system was built around a queue-first architecture using RabbitMQ and Redis Streams for workload separation and retries. Notifications were dispatched via worker pools that supported channel-specific backoffs, dead-lettering, and logging. Each notification event flowed through the following stages:

Received via internal event bus or API

Persisted and queued with metadata and user preferences

Routed to workers per channel (email, SMS, push, etc.)

Delivery tracking with feedback from external providers

I also implemented idempotency guarantees, template rendering, and per-tenant throttling rules, ensuring notifications were both reliable and context-aware.

All of this was observable via a metrics dashboard (Grafana + Prometheus), including per-channel success rates and latency heatmaps.

Key Skills: RabbitMQ, Redis Streams, Worker Pools, Event-Driven Architecture, Multichannel Notification

Problem Solved: Delivered a resilient, scalable, and extensible notification pipeline for high-volume messaging across multiple delivery channels.