RoadPulse

Ambulances lose minutes in traffic because drivers find out too late. Radius-based "nearby" alerts notify everyone around, so people learn to ignore them.

A relevance engine on the road network: a driver is alerted only when they are ahead of the ambulance on the same carriageway, waiting at a junction it will cross, or oncoming on an undivided road. Alerts escalate with distance and clear once the ambulance has passed.

• Expo / React Native app with two modes: anonymous driver mode and authenticated emergency-operator mode
• NestJS modular monolith; PostgreSQL + PostGIS for the road graph, map matching and spatial queries
• A* routing over the stored road network, so routes and relevance use the same roads
• Alert lifecycle: NORMAL → HEAVY → IMMEDIATE by road distance, resolved automatically once passed
• MapLibre GL + OpenFreeMap in a WebView — no map API key, same map on phone and web

• Deciding relevance on roads, not radii: divided carriageways, junctions and direction of travel all change who should be warned.
• Never encouraging unsafe driving: every alert says "give way when safe", never "speed up" or "jump the signal".

your role on RoadPulse

Working prototype, tested end to end on a simulated road network. Next: real road data from OpenStreetMap, traffic-police alerts at signals, and alerts in Hindi.