Design Scheduled Rides - System Design | WinJob

Problem Statement: Advance-Booked Rides

Riders book 15 minutes to 7 days ahead; system locks quoted fare and promises on-time pickup for premium tiers. advance-booked ride platform (Uber Reserve / Lyft Scheduled): riders lock pickup time and fare; a Reservation Ledger commits bookings; a Dispatch Planner assigns drivers in a pre-pickup window (T-30 to T-5); on-demand matching stays separate to protect p99 ETAs.

Mechanism (1)

Riders book 15 minutes to 7 days ahead; system locks quoted fare and promises on-time pickup for premium tiers.

Operational signals

Watch on_time_pickup_rate, planner_lag_sec, soft_hold_expiry_rate, fare_lock_dispute_rate, dispatch_retry_count. Page when on_time_pickup_rate drops below 97% for 30 minutes in any tier-1 airport market.

javaOne Dark Pro

1 public final class ReservationCmd1 {
2   private final String reservationId;
3   private final long reservationVersion;
4   private final String pickupMarketId;
5   private final Instant pickupAt;
6   public String reservationId() { return reservationId; }
7 }

pythonOne Dark Pro

1 @dataclass(frozen=True)
2 class ReservationCmd1:
3     reservation_id: str
4     reservation_version: int
5     pickup_market_id: str
6     pickup_at: datetime

typescriptOne Dark Pro

1 interface ReservationCmd1 {
2   reservationId: string;
3   reservationVersion: number;
4   pickupMarketId: string;
5   pickupAt: string;
6 }

Why interviewers care

Scheduled Rides interviews reward crisp scope, explicit trade-offs, and failure stories—not generic microservice diagrams.

Interview checkpoint

Name one failure story for Problem Statement: Advance-Booked Rides that proves you understand real outages, not happy-path diagrams.

Key Highlights

•Anchor 1-A: reservation ledger owns writes
•Anchor 1-B: pickup_market + pickup_week partition
•Anchor 1-C: pre-dispatch planner with soft holds
•Anchor 1-D: on_time_pickup_rate SLO

1	public final class ReservationCmd1 {
2	private final String reservationId;
3	private final long reservationVersion;
4	private final String pickupMarketId;
5	private final Instant pickupAt;
6	public String reservationId() { return reservationId; }
7	}

1	@dataclass(frozen=True)
2	class ReservationCmd1:
3	reservation_id: str
4	reservation_version: int
5	pickup_market_id: str
6	pickup_at: datetime