What it does
A notification service is a shared system that accepts events from many producers and turns them into messages delivered to users. Instead of every product team building its own email and push code, they call one well defined interface.
The core pieces
- An ingestion API or queue where producers submit notification requests.
- A processing layer that applies preferences, templates, and rate limits.
- A set of channel workers that talk to email, SMS, and push providers.
- A status store that records what was sent and what failed.
Why centralize
- One place to enforce opt outs and compliance rules.
- Shared retry and deduplication logic instead of copies everywhere.
- A single view of deliverability across the company.
The service is the boundary between business events and the messy details of delivering bytes to a phone or inbox.
Key idea
A notification service centralizes preferences, templates, and delivery so teams send messages through one reliable path.