GangForCode

Retrieval-Augmented Generation (RAG) has become one of the most important architectures for building production-grade Generative AI applications. From enterprise chatbots and document Q&A systems to AI search engines and knowledge assistants, RAG allows Large Language Models (LLMs) to generate responses using external, up-to-date, and domain-specific information. If you are preparing for an AI Engineer, Machine … Read more

Decorators are one of Python’s most powerful features—and also one of the most commonly asked topics in Python interviews. Whether you’re learning Python for the first time, preparing for a FastAPI or Django interview, or trying to understand how frameworks like Flask and FastAPI work internally, decorators are an essential concept to master. You have … Read more

The Singleton design pattern sounds simple — “one instance, one class.” But if an interviewer gives you five minutes and a whiteboard, the real depth reveals itself fast. Thread safety, memory model guarantees, reflection attacks, serialization loopholes, classloader edge cases, and how Spring quietly replaces the whole thing. This guide covers everything a senior Java … Read more