HLD: Design a Ride-Sharing App

Designing a ride-sharing service like Uber requires solving Hyper-local Routing at scale.

Geographic Indexing

Querying millions of driver coordinates in real-time is impossible with standard DB indexes. Use QuadTrees or Google S2 / Geohash libraries to partition the Earth into grid cells.

Data Flow

1. Driver sends location update every ~5s.
2. Ride matching service queries QuadTree for nearby drivers.
3. WebSockets used for real-time driver movement on the rider's map.