LangChain
A Python/JS framework for chaining LLM calls, tools, memory, and retrievers into production AI applications and agents.
LangChain is the most widely adopted framework for building LLM-powered applications. It provides abstractions for chaining model calls, integrating external tools and APIs, managing conversational memory, and building retrieval-augmented generation (RAG) pipelines. LangSmith (its observability layer) and LangGraph (for agent workflows) have extended it into a broader ecosystem for production AI development.
Typical time to job-readiness: ~4 weeks.