Real-time Driver Location Tracking in .NET: Redis GEO, Channels and SignalR

Every four seconds, every active Uber driver sends their GPS coordinates to a server. At peak, that's roughly 5 million updates per minute — before you even count the riders watching their driver move on a map in real time. The location pipeline is the heartbeat of the entire platform. If it slows down, drivers and riders fall out of sync. If it falls over, the app is effectively useless. Building something like this in .NET is a good exercise in knowing when not to reach for a database. Locatio