System Design Interview: API Rate Limiting and Throttling
12 min read Why Rate Limiting? Rate limiting protects services from overload, abuse, and cost explosions. Without it: a single misbehaving client can […] Read article
System Design
Algorithms
Scala Interview Questions: Functional Programming, Case Classes, and Akka (2025)
10 min read Scala Interview Overview Scala is the language of Apache Spark, Kafka (originally), Akka, and many financial systems. Interviews at data Read article
System Design
System Design Interview: Log Aggregation and Observability Pipeline
10 min read Why Log Aggregation? With hundreds of microservices each running multiple replicas, logs are scattered across thousands of containers. Without centralized Read article
System Design
System Design Interview: Secret Management and PKI (Vault, AWS Secrets Manager)
10 min read Why Secret Management Matters Secrets (database passwords, API keys, TLS certificates, SSH keys) are the crown jewels of any system. Read article
System Design
System Design Interview: Multi-Region Active-Active Architecture
10 min read Why Multi-Region Active-Active? A single-region active-passive setup (one primary region serves traffic, one standby region for failover) has two problems: Read article
Algorithms
Hash Table and HashMap Interview Deep Dive
4 min read Why Hash Tables? Hash tables provide O(1) average-case lookup, insertion, and deletion — making them the most versatile data structure Read article
System Design
System Design Interview: Global Content Delivery and Edge Computing
10 min read Beyond Basic CDN: Edge Computing A CDN (Content Delivery Network) has historically served static assets — images, CSS, JS — Read article
Algorithms
PHP Interview Questions (2025): OOP, Performance, and Modern PHP
4 min read PHP Interview Questions Overview PHP powers 77% of websites with a server-side language (including WordPress, Facebook’s HHVM era, Shopify’s partner Read article
System Design
System Design Interview: Kubernetes Autoscaling (HPA, VPA, KEDA, and Cluster Autoscaler)
9 min read Why Autoscaling? Manual capacity planning is expensive and error-prone. Too much capacity wastes money; too little causes outages under traffic Read article
System Design
System Design Interview: Two-Phase Commit and Distributed Transactions
10 min read The Distributed Transaction Problem A transaction that spans multiple databases or services must either fully commit on all participants or Read article
System Design
System Design Interview: Data Warehouse and OLAP Architecture
10 min read What Is a Data Warehouse? A data warehouse (DW) is an analytical database optimized for reading large volumes of historical Read article
Algorithms
String and Array Manipulation Interview Patterns
4 min read String and Array Patterns Overview String and array manipulation problems are a staple of coding interviews at every level. The Read article
System Design
System Design Interview: Service Mesh and Microservice Communication
9 min read What Is a Service Mesh? A service mesh is a dedicated infrastructure layer for managing service-to-service communication in a microservices Read article
System Design
System Design Interview: Zero-Downtime Deployments
10 min read Why Zero-Downtime Deployments Planned downtime windows are increasingly unacceptable — global users span every time zone, and even brief outages Read article
Algorithms
Ruby on Rails Interview Questions (2025)
5 min read Rails Interview Questions Overview Ruby on Rails powers Shopify, GitHub (partially), Airbnb, and many startups. Senior Rails interviews test deep Read article
