📌 links that will scale your knowledge here (visual explanations and diagrams are 🔥 there so have a look as this is smth you’ll need in your interviews):

we are building a system which keeps its users informed about important events. It's more than just popping up alerts; it's about delivering the right information, to the right person, at the right time.

Why are Notification Systems Important?

Notifications are the lifeblood of user engagement in many applications. They:

Key Components: The Notification Pipeline

At the heart of any notification system lies a pipeline. Think of it as an assembly line where each step plays a role in getting the notification out to the user:

  1. Event Generation: The trigger that starts the whole process. Something happens in the system (e.g., a user posts a comment).
  2. Notification Creation: The raw data is transformed into a notification object, specifying the type of notification, the target user(s), and the message content.
  3. Routing: The notification needs to be directed to the correct delivery channel(s) (e.g., push notification, email, SMS, in-app alert).
  4. Delivery: The actual sending of the notification through the chosen channel. This involves interacting with different services (e.g., APNs for iOS push, FCM for Android push, SendGrid for email).
  5. Feedback & Analytics: Tracking the delivery status and user interaction with notifications is vital for optimization. Did the user receive it? Did they open it?

Design Considerations: The Devil's in the Details

It's not just about sending alerts; it's about doing it well. Here are key design points: