This article was originally published on AI Study Room . For the full version with working code examples and related articles, visit the original post. LangChain vs LlamaIndex vs Haystack (2026): AI Framework Comparison Building LLM applications requires a framework to manage prompts, chains, retrieval, and agent orchestration. In 2026, three frameworks dominate: LangChain (the most popular, general-purpose), LlamaIndex (specialized in data indexing and RAG), and Haystack (NLP pipelines, from deepset). Choosing the right one depends on whether you are building agents, search systems, or document processing pipelines.…