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SYSTEM DESIGNDesign Amazon (E-Commerce Checkout)AmazonShopifyWalmart

TRAFFIC LEVEL

—/3

CONSTRAINTS

Peak orders/minute100,000

Inventory items1B SKUs

Payment provider SLA99.9% success rate

Double-charge toleranceZero

Checkout timeout30 seconds

Compute & Network

Load BalancerDistribute traffic

API GatewayEntry point / auth

API ServerBusiness logic

Worker NodeAsync processing

CDN EdgeGlobal cache

WebSocket GatewayPersistent connections

Data Stores

PostgreSQLRelational DB

MySQLRelational DB

CassandraWide-Column DB

DynamoDBNoSQL / Managed

S3 BucketObject storage

Queues & Cache

Redis CacheIn-memory store

KafkaEvent stream

ZookeeperCoordination

Specialized

Bloom FilterProbabilistic set

Rate LimiterThrottling

Geohash ServiceGeospatial index

Trie ServerPrefix search

APNS / FCMPush notifications

AggregatorBatch / roll-up

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🚨 INCIDENT

AmazonShopifyWalmart

Design Amazon's checkout and order processing flow. A customer adds items to cart, proceeds to checkout, confirms the order, and payment is charged. The system must handle 100k orders/minute at peak (Black Friday), ensure inventory is not oversold, and process payments reliably even if services fail mid-flow.

📥 Assigned to:You — Senior Engineer

SCALE LEVELS

10,000 RPS

Target: <2000ms

50,000 RPS

Target: <1000ms

100,000 RPS

Target: <500ms

GLOBAL SUCCESS RATE

100.0%

P99 LATENCY

45ms

Target: < 200ms

TOTAL RPS INGESTED0 / 11,000