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Startups14,448Programs29

14,448 startups · 29 programs

assistant-ui

Active · Open Source React.js Library for AI Chat

WebsiteYC profile

Why it ranks

How the rank works
7signal of 100 · rising 4
  • went through YCProgram · this site+4
  • team of 3Team size · YC's directory+3.1

A sum of public facts, not a judgement and not investment advice.

Competitors

AIInactiveAtlaShared: popular agent, agent framework, langchainYC S23LondonStartup →AIAdenShared: open, source, frameworkYC W20San FranciscoStartup →DataQuillShared: react libraryYC W20San FranciscoStartup →
Companies closest to assistant-ui
Company
AtlaShared: popular agent, agent framework, langchainYC S23InactiveAI, Data, Devtools
AdenShared: open, source, frameworkYC W20ActiveAI, Devtools
QuillShared: react libraryYC W20ActiveData, Devtools

Adjacent

DataAcquiredTremorShared: web development, reactYC S23ZugStartup →OtherHarmonizeShared: chatAlchemist Class 23New YorkStartup →OtherAcquiredGuildedShared: chatYC S17San FranciscoStartup →Developer toolsAppwriteShared: open, source, backendSeedcamp 2020Startup →AILinzumiShared: chat, source, dozenYC X26San FranciscoStartup →
Companies next to assistant-ui
Company
TremorShared: web development, reactYC S23AcquiredData, Devtools
HarmonizeShared: chatAlchemist Class 23Not statedOther
GuildedShared: chatYC S17AcquiredOther
AppwriteShared: open, source, backendSeedcamp 2020Not statedDevtools
LinzumiShared: chat, source, dozenYC X26ActiveAI, Devtools

Also from W25 in AI

All of W25
AIDextoAWS for AI AgentsYC W25San FranciscoStartup →AIa0.devWe make mobile apps using AI.YC W25San FranciscoStartup →AIArtilLet your agents message teammates and other agentsYC W25LondonStartup →AICodevisorThe fastest native app for agentic engineering.YC W25San FranciscoStartup →AIConfident AIProduction Monitoring & Evals for AI AgentsYC W25San FranciscoStartup →AICorsairOpenRouter for IntegrationsYC W25New York CityStartup →
Company
DextoAWS for AI Agentsteam of 2ActiveAI, Devtools
a0.devWe make mobile apps using AI.team of 3hiringActiveAI, Devtools
ArtilLet your agents message teammates and other agentsteam of 2ActiveAI, Devtools
CodevisorThe fastest native app for agentic engineering.team of 2ActiveAI, Devtools
Confident AIProduction Monitoring & Evals for AI Agentsteam of 7hiringActiveAI, Devtools
CorsairOpenRouter for Integrationsteam of 2ActiveAI, Devtools

Founders

  • Simon FarshidFounder/CEO

About assistant-ui

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.

YC batch
W25 · Winter 2025
Status, per YC
Active
Category
AI, Developer tools
Team size
3
Location
San Francisco, CA, USA
Founded
2024
Checked
6h ago

YC tags: Developer Tools, Generative AI, Chat, Web Development, AI Assistant

assistant-ui in W25: 166 companies, 84% AI

GitHub LinkedIn

assistant-ui: questions

Which YC batch was assistant-ui in?

assistant-ui was in Y Combinator's Winter 2025 batch (W25).

Is assistant-ui still active?

Y Combinator lists assistant-ui as active.

Who founded assistant-ui?

assistant-ui's founders, as listed on its YC page: Simon Farshid (Founder/CEO).

Where is assistant-ui based?

assistant-ui lists San Francisco, CA, USA as its location on YC's directory.