Dear Stack Experts,

I was asked in an interview recently to design ride/driver location tracking feature of Uber. I could come up with simple design constituting of data bases i.e., Cassandra(Write driver location), MySQL( InTrip ), Redis(Websocket & Segment Location Management). Then I fleshed out WebSocket Handler, WebSocket Manager, Location Track Service. But reading online my design would probably get 5/10 points(B- grade). The best online solution is building Distributed Car Location Index, one can’t simply derive this from hints or key points. If anyone has solved this in an interview, I’d love hear from you what components and how would you fine tune the location update aspect. Both are quite tangential solutions for designing Uber location tracking.

Simple put would you give more points to MapReduce design(due to complexity) or Data Store & Service Layered approach (simple scratching the surface).