assistant-ui helps frontend developers add AI chat to their apps. Our product is used by several dozen companies, like LangChain, Stack AI, Browser Use, and Athena Intelligence.
assistant-ui is a Y Combinator company in the Winter 2025 batch. Its directory entry describes it as: Open Source React.js Library for AI Chat. The founder listed is Simon Farshid (Founder/CEO) (Y Combinator directory entry, February 6, 2025).
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New accelerator entry · 2025-02-06 · the record
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assistant-ui helps frontend developers add AI chat to their apps. Our product is used by several dozen companies, like LangChain, Stack AI, Browser Use, and Athena Intelligence. We're building an open source Typescript/React library and a backend as a service, with first class integrations into popular agent frameworks like LangGraph and Vercel AI SDK.
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