Backend Interview Preparation Hub

Your structured, interview-oriented guide to mastering backend development, system design, and core computer science concepts.

120+ Articles
12 LLD Problems
7 System Designs
200+ Interview Q&As
Core Java & OOPs

Deep-dive into JVM, memory management, multithreading, collections, exception handling, and Java 8+ features with interview-ready answers.

System Design

Learn building blocks like load balancers, caches, queues, and CDNs. Practice with real-world designs for YouTube, WhatsApp, and more.

Low-Level Design

12 classic LLD problems with full Java implementations — parking lot, elevator, vending machine, cache system, and more.

Microservices & Spring Boot

From monolith-to-microservices migration to service discovery, configuration management, and production-ready Spring Boot patterns.

Databases & Caching

SQL vs NoSQL decision guide, Redis, Elasticsearch, DynamoDB — understand when and why to pick each technology.

Last-Week Interview Revision

Curated masterlist of 200+ frequently asked Q&As across Java, microservices, Spring Boot, Kafka, AWS, and distributed systems.

How to Use This Resource
  • Browse by topic — Use the sidebar to navigate through Java, System Design, LLD, Microservices, and more.
  • Search instantly — Press Ctrl+K to search across all topics.
  • Interview-first approach — Every article is structured as Q&A with concise, interview-ready answers.
  • Last-week revision — Use the Interview Masterlist section for rapid revision before your interview.