LangExtract is a Python library for extracting structured information (entities, relationships) from unstructured text using large language models (LLMs). It provides a production-grade pipeline: chunking long documents, building prompts with few-shot examples, invoking LLMs (Gemini, OpenAI, Ollama, or custom providers), parsing and fuzzy-aligning the output to source text, and generating interactive HTML visualizations. The architecture is modular with a plugin system for providers, a schema system for output constraints, and a resolver for alignment. It includes comprehensive tests, benchmarks, and CI/CD. The library is actively maintained with a clear deprecation path for v2.0.0. Notable strengths are the provider plugin system, fuzzy alignment algorithms, and format handling. Weaknesses include some deprecation debt and complex alignment code.