📝 System Design Interview Classics · C4 Architecture · Pro
Ride Matching System (Uber-style)
The core of a ride-hailing app: drivers stream their locations, a geo index finds nearby drivers, and a matching service offers the trip to the best one.
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Drawing diagram…
What this diagram shows
- Driver locations are updated every 4 seconds into a geo index
- Matching offers the trip to one driver at a time with a timeout
- Trips and payments are handled by separate services
Prompt used
Ride-hailing design: driver apps send GPS every 4 seconds to a location service that updates a geospatial index in Redis (geohash). Rider apps request a trip through the trip service. The matching service finds nearby available drivers, ranks them by ETA and offers the trip to one driver at a time. Accepted trips are stored in PostgreSQL. A pricing service computes fare and surge, and a payment service charges the rider at the end.
Mermaid code
C4Container
title Ride Matching
Person(rider, "Rider", "Requests trips")
Person(driver, "Driver", "Accepts trips")
System_Boundary(rh, "Ride Platform") {
Container(loc, "Location Service", "Go", "Ingests driver GPS")
ContainerDb(geo, "Geo Index", "Redis GEO", "Available drivers by area")
Container(trip, "Trip Service", "Java", "Trip requests and status")
Container(match, "Matching Service", "Go", "Finds and offers best driver")
Container(price, "Pricing Service", "Python", "Fare and surge")
Container(pay, "Payment Service", "Java", "Charges riders")
ContainerDb(db, "Trip DB", "PostgreSQL", "Trips and history")
}
System_Ext(maps, "Maps API", "Routes and ETA")
Rel(driver, loc, "GPS every 4 s", "WebSocket")
Rel(loc, geo, "Updates position")
Rel(rider, trip, "Requests trip", "HTTPS")
Rel(trip, price, "Gets fare")
Rel(trip, match, "Find driver")
Rel(match, geo, "Nearby drivers")
Rel(match, maps, "ETA")
Rel(match, driver, "Trip offer")
Rel(trip, db, "Saves trip")
Rel(trip, pay, "Charge at end")Related templates
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