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Practice Problems

Sharpen your skills with real-world coding challenges covering architecture, debugging, integration, and system tradeoffs.

Build vs Buy: When to Use Third-Party Services

architecture-decisionbuild-vs-buyvendor-lock-in+2

Strong vs Eventual Consistency

consistencycap-theoremdistributed-systems+2

REST vs GraphQL: Making the Right Choice

api-designrestgraphql+2

Monolith vs Microservices for a Startup

architecturemicroservicesmonolith+2

SQL vs NoSQL: Choosing Your Database

databasessqlnosql+2

Integrate Multi-Provider Email Service

emailfailovercircuit-breaker+2

Build a Saga Pattern for Order Processing

saga-patterndistributed-transactionsmicroservices+2

Integrate Real-Time WebSocket Updates

websocketsreal-timescaling+2

Build an Idempotent API Endpoint

idempotencyapi-designreliability+2

Integrate OAuth 2.0 Login Flow

oauthauthenticationsecurity+2

Integrate Stripe Webhook Handling

stripewebhookspayments+2

Debug Intermittent 502 Errors Under Load

load-balancinghealth-checksdebugging+2

Debug Distributed Deadlock

distributed-systemsdeadlockdebugging+2

Debug Race Condition in Concurrent Updates

concurrencyrace-conditiondatabases+2

Debug Memory Leak in Express Middleware

memory-leaknode.jsexpress+2

Debug Connection Pool Exhaustion

databasesconnection-pooldebugging+2

Fix the N+1 Query Problem

databasesormperformance+2

Design a Real-Time Collaborative Editor

real-timecrdtoperational-transform+2

Design a Distributed Rate Limiter

distributed-systemsrate-limitingredis+2

Design a Multi-Tenant Database Schema

multi-tenancydatabase-designsecurity+2

Design an Event Notification System

pub-subnotificationsevent-driven+2

Design a Job Queue System

queuesbackground-jobsreliability+1

API Gateway Routing Design

api-gatewaymicroservicesrouting+1

Design a Simple Key-Value Cache

cachingdata-structuresmemory-management+1

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