Companies and Developers Using LangChain
LangChain is the most-adopted open-source framework for building LLM applications, used at Microsoft, LinkedIn, Uber, Elastic, and thousands of AI and RAG products.
By the numbers
| Metric | Value |
|---|---|
| GitHub stars | 133.9k |
| Forks | 22.1k |
| Contributors | 3,670+ |
| Latest release | Apr 2026 |
Source: GitHub · fetched 2026-04-17
What is LangChain?
LangChain is a framework for building applications with large language models, released in late 2022 by Harrison Chase. It is MIT licensed and available in both Python and TypeScript. It provides abstractions for LLM calls, prompt templates, output parsers, tool use, agents, retrieval pipelines, vector stores, and memory, with hundreds of integrations across model providers and data sources.
The LangChain ecosystem has grown into several distinct products: LangChain (the framework), LangGraph (stateful agent orchestration), LangSmith (hosted observability and eval platform), and LangServe (deployment). LangGraph in particular became the go-to framework in 2024–2026 for building production agents with explicit state machines, loops, and human-in-the-loop checkpoints.
Who uses LangChain?
Public LangChain and LangGraph adopters include Microsoft, LinkedIn, Uber, Elastic, Klarna, Replit, Morningstar, Ally Financial, and Retool. LangGraph specifically is used inside LinkedIn’s recruiter AI, Uber’s internal assistants, Elastic’s AI Assistant, and many enterprise agentic systems. Usage is heaviest in RAG pipelines, internal agents, and customer-facing copilots.
LangChain users are AI/ML engineers building agents and RAG systems, backend engineers wiring LLMs into applications, data scientists prototyping pipelines, and platform engineers running LLMOps infrastructure. These personas buy LLM APIs, vector databases (Pinecone, Weaviate, pgvector), observability (LangSmith, Arize, Langfuse), and GPU hosting.
According to the LangChain README: “LangChain is a framework for building agents and LLM-powered applications.” (source)
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Frequently asked questions about LangChain
What companies use LangChain?
LangChain is used in production at Replit, Elastic, IBM, and hundreds of AI-first startups using LangChain to orchestrate multi-step LLM pipelines, agents, and RAG applications.
Who maintains LangChain?
LangChain, Inc., founded by Harrison Chase and others in 2022. The LangChain Python and JavaScript libraries are MIT licensed. The company also maintains LangSmith (observability) and LangGraph (stateful agents) as commercial products.
What are alternatives to LangChain?
LlamaIndex (data-centric RAG focus), LangGraph (LangChain’s own stateful agent graph layer), CrewAI (multi-agent), AutoGen (Microsoft, multi-agent), and the Vercel AI SDK for TypeScript streaming.
How many developers contribute to LangChain?
LangChain has 3,670 contributors (GitHub, 2026/04). It is one of the more actively contributed open-source projects in its category, with contributions from both individual developers and corporate engineering teams.
Is LangChain production-ready?
Yes. LangChain is production-ready: it has 133.9k GitHub stars, 3,670 contributors (GitHub, 2026/04), and is last released Apr 2026. It is used in production at large-scale organizations and has a mature release cadence.
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