Design Grab or Gojek (Super App) - System Design | WinJob

Problem Statement: Grab/Gojek Super-App

Design Grab/Gojek-class super-app architecture: shared identity, integrated wallet, and isolated vertical domains (mobility, food, payments). This section covers problem statement: grab/gojek super-app in the understanding phase.

Operational detail

State numbers before boxes: MAU, peak location writes, ledger TPS, and country shard boundaries. When challenged on super-app coupling, show platform services (identity, wallet, notify) versus vertical services (ride, food) with explicit failure isolation.

Failure and edge cases

Unique to sec-01: wallet double-spend on retry, stale driver cell after partition move, food order paid but merchant offline, cross-border FX rounding disputes.

Interview checkpoints

javaOne Dark Pro

1 public record GrabContext(String userId, String countryCode, String vertical) {
2   public boolean requiresWalletHold() { return "pay".equals(vertical) || "food".equals(vertical); }
3 }

pythonOne Dark Pro

1 def surge_multiplier(demand: int, supply: int) -> float:
2     if supply == 0:
3         return 3.0
4     ratio = demand / max(supply, 1)
5     return min(2.5, 1.0 + 0.25 * ratio)

typescriptOne Dark Pro

1 export function walletDebitAllowed(balance: number, hold: number, amount: number): boolean {
2   return balance - hold >= amount;
3 }

Why interviewers care

Grab or Gojek (Super App) interviews reward crisp scope, explicit trade-offs, and failure stories—not generic microservice diagrams.

Interview checkpoint

Name one failure story for Problem Statement: Grab/Gojek Super-App that proves you understand real outages, not happy-path diagrams.

Key Highlights

•multi-vertical ecosystem in one mobile shell
•integrated GrabPay/GoPay wallet as money rail
•motorcycle-first mobility in dense ASEAN cities
•cross-vertical identity and loyalty graph

1	public record GrabContext(String userId, String countryCode, String vertical) {
2	public boolean requiresWalletHold() { return "pay".equals(vertical) \|\| "food".equals(vertical); }
3	}

1	def surge_multiplier(demand: int, supply: int) -> float:
2	if supply == 0:
3	return 3.0
4	ratio = demand / max(supply, 1)
5	return min(2.5, 1.0 + 0.25 * ratio)

1	export function walletDebitAllowed(balance: number, hold: number, amount: number): boolean {
2	return balance - hold >= amount;
3	}