What is Sightscreen?
Sightscreen is a real-time cricket live-scoring platform. It pulls fixture and scoring data from external APIs, detects match events through an event-driven pipeline, builds display state, and pushes updates to users via an iOS app with Live Activities and push notifications. The platform has three main surfaces:- iOS App — SwiftUI app with Live Activities (ActivityKit) for ball-by-ball match tracking
- Backend API — Express/TypeScript service running on Node.js, built around an event-driven architecture for real-time match processing and APNs delivery
- Pavilion — iOS admin app for managing fixtures, leagues, and monitoring system health
Tech stack
Architecture at a glance
The backend follows an event-driven architecture (LA v2). Instead of monolithic polling jobs that detect changes and push updates in one pass, the system separates concerns into a pipeline:- ScorePoller / MarqueePoller fetch data from SportMonks
- MatchEventBus routes raw data through the event detection pipeline
- Tier0 / Tier1 detectors classify events by importance
- CooldownFilter / StalenessFilter suppress noise
- LACoordinator coordinates APNs delivery with priority management
- MatchOrchestrator manages the full match lifecycle
What this docs site is for
This is an internal living architecture map. It exists so any developer working on Sightscreen can:- Quickly understand how the system fits together
- Find which service owns a given responsibility
- Trace data flow from external APIs to the user’s screen
- Debug production issues without reading every source file first
This is not public documentation. It is a working reference that should be updated as the system evolves.