Google Maps — Simple

Problem statement (interviewer prompt)

Design Google Maps: serve global vector + raster tiles at sub-100ms p99, run point-to-point routing with live traffic ETAs in <500ms, handle place search + geocoding, and ingest billions of anonymised GPS probes per day to estimate live speeds.

flowchart LR
  U([User])
  TILES[Map Tile Service]
  ROUTE[Routing Service]
  PLACES[Places / Geocoder]
  TRAFFIC[Traffic Service]
  ETA[ETA Engine]
  U --> TILES
  U --> ROUTE --> ETA
  U --> PLACES
  TRAFFIC --> ROUTE

    classDef client fill:#dbeafe,stroke:#1e40af,stroke-width:1px,color:#0f172a;
    classDef edge fill:#cffafe,stroke:#0e7490,stroke-width:1px,color:#0f172a;
    classDef service fill:#fef3c7,stroke:#92400e,stroke-width:1px,color:#0f172a;
    classDef datastore fill:#fee2e2,stroke:#991b1b,stroke-width:1px,color:#0f172a;
    classDef cache fill:#fed7aa,stroke:#9a3412,stroke-width:1px,color:#0f172a;
    classDef queue fill:#ede9fe,stroke:#5b21b6,stroke-width:1px,color:#0f172a;
    classDef compute fill:#d1fae5,stroke:#065f46,stroke-width:1px,color:#0f172a;
    classDef storage fill:#e5e7eb,stroke:#374151,stroke-width:1px,color:#0f172a;
    classDef external fill:#fce7f3,stroke:#9d174d,stroke-width:1px,color:#0f172a;
    classDef obs fill:#f3e8ff,stroke:#6b21a8,stroke-width:1px,color:#0f172a;
    class U client;
    class TILES,ROUTE,PLACES,TRAFFIC,ETA service;