System Design·60 minMembers

Notification System

Members only

Design Reddit's notification system: deliver in-app, push, and email notifications for events like replies, mentions, mod actions, and trending posts. Supports per-user preferences, bundling/digesting...

SWE

notification

push-notification

fan-out

messaging

scaling

medium

Frequency

Low

Last asked

2026-04-12

Stage

onsite-system-design