Realtime is a real-time data distribution and synchronization engine that enables applications to stream database changes and coordinate state between clients. It functions as a synchronization layer that monitors database write-ahead logs to provide change data capture and pushes updates to authorized clients via WebSockets.
The project features a real-time presence server for tracking the online status of active users and a broadcast service for sending ephemeral messages without database persistence. It organizes communication through channel-based message routing and uses a structured JSON protocol to manage subscriptions and broadcasts.
The system integrates row-level security to enforce data access controls during the streaming process and supports logical replication to stream row-level modifications. Its capability surface extends to shared state synchronization and the implementation of real-time chat infrastructure.