ENGINEERING NOTE / 05
Real-time messaging in Pulse
Pulse connects persistent chat data to live delivery. The design keeps access control, recovery, and device behavior in view alongside WebSockets.
In this note 03 questions
What does a WebSocket add?
It delivers messages and state changes while a conversation is open. Persistent storage still supplies history, pagination, and recovery after a connection drops.
How are private files protected?
The server checks conversation membership before serving an attachment. A private upload path is not made public simply because the message UI can display it.
What happens on Android in the background?
The Android app uses the same web conversation interface and checks periodically for unread messages while closed. That is a scheduled check, not instant push delivery.