Design 3-Day Charity Donation Service — DoorDash — Intervues

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Design 3-Day Charity Donation Service[ OK ] 251 — full content available
[ INFO ] category: System Design  difficulty: hard  freq: high  first seen: 2026-01-13
[HARD][SYSTEM DESIGN][HIGH]data_engineeringIdempotencywebAsync Processingmachine_learningPaymentSystem Designmobilebackend
$ cat problem.md
Design a donation service for a 3-day charity event.
Requirements:
Accept donations from users (various amounts)
Integrate with 3rd party payment processor
Handle payment failures gracefully
Ensure idempotency (prevent duplicate donations)
Scale for high traffic during event
Key Components:
API Gateway with rate limiting
Donation Service (handles donation logic)
Payment Service (3rd party integration)
Message Queue for async processing
Database for persistence
Discussion Points:
Idempotency keys to prevent duplicates
Async vs sync payment processing
Retry strategies for failed payments
Dead letter queues for unprocessable payments
Scalability during peak times
Transaction isolation levels
user@intervues:~/doordash$ 