Saga Pattern for Distributed Transactions in Microservices
When a single business operation spans multiple microservices, you lose the safety net of database transactions. A monolith can wrap...
Message Queues Compared: RabbitMQ vs Kafka vs AWS SQS
Message queues decouple producers from consumers, absorb traffic spikes, and enable asynchronous processing — but choosing the wrong one creates...
Caching Strategies: Write-Through, Write-Behind, and Cache-Aside
Caching is one of the most effective ways to improve application performance, but choosing the wrong caching strategy can introduce...
Database Sharding Strategies: Horizontal vs Vertical Partitioning
Eventually, every growing application hits a point where a single database server cannot keep up. Queries slow down, write throughput...
System Design Interview: Designing a Rate Limiter
Every production API needs a rate limiter. Without one, a single misbehaving client — whether malicious or simply buggy —...
System Design Interview: Designing a Chat Application
Real-time messaging is one of the most demanding system design problems because it combines persistent connections, low-latency delivery, message ordering,...
System Design Interview: Designing a URL Shortener
The URL shortener is one of the most common system design interview questions, and for good reason. It sounds deceptively...
Two-Factor Authentication (2FA) Implementation Guide
Passwords alone no longer provide adequate protection for user accounts. Credential stuffing attacks, phishing, and database breaches make single-factor authentication...
Secrets in Code: How to Detect and Prevent Leaked Credentials
Hardcoded secrets in code are one of the most common and preventable security vulnerabilities. API keys, database passwords, private tokens,...