Problems

Each problem is a small multi-file project with seeded bugs (or a missing feature), visible tests and hidden tests. Pick one, fix it, and submit. Problems marked Sign in need a free account.

• 11

  11API Gateway Rate Limiter

  API gateway rate limiter (token buckets, request log CSV)

  C++EasyBug fix60 min
• 12

  12Review Moderation Rules

  Product review moderation rules (review export, word lists, queue)

  C++EasyBug fix60 min
• 13

  13Putaway Bin Allocator

  Warehouse putaway bin allocator (best fit, zone usage)

  C++EasyBug fix60 min
• 14

  14Loyalty Points Calculator

  Loyalty points calculator (implement pointsForOrder; tiers, redemptions)

  C++EasyFeature60 min
• 15

  15Return Routing Engine

  Return routing engine (restock/vendor/liquidation/disposal, warehouse choice, batch retries)

  C++MediumBug fix60 min

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• 16

  16Catalog Cache Service

  Catalog LRU/TTL cache (read-through service, TTL policy, metrics)

  C++MediumBug fix60 min

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• 17

  17Driver Shift Planner

  Driver shift planner (implement chooseDriver; rest rule, daily max)

  C++MediumFeature60 min

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• 18

  18Fast Delivery Eligibility Checker

  Fast-delivery eligibility checker (JSON feed, longest-prefix regions, cutoffs, carts)

  C++MediumBug fix60 min

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• 19

  19Return Fraud Risk Scoring

  Return-fraud risk scoring (dates, weighted factors, tier share, retries)

  C++HardBug fix60 min

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• 20

  20Subscription Renewal Billing

  Subscription renewal billing (implement prorationCharge; anchors, retries, transitions)

  C++HardFeature60 min

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