EDUCATION & TRAINING
Which Python AI Framework to Choose (2026)
Dev.to Machine Learning
About This Tutorial
Choosing between LangChain and LlamaIndex is one of the first decisions you face when building a Python AI application in 2026. Both frameworks accelerate LLM development, both are open source, and both have active communities - but they solve different problems. pro What Is LangChain? LangChain is a framework for building applications powered by language models. Its core idea is composability: you chain together prompts, models, tools, memory, and agents using a unified interface called LCEL (LangChain Expression Language.