UI Library GitHub Repositories (2026) · Open Source Tools

UI for AI agents. React components for what agents do – agent trees, tool calls, traces, handoffs and approvals – and for the rest of your app. One file each, install with shadcn or via MCP. Free and open source.

🌼 🌼 🌼 🌼 🌼  The most popular, free and open-source Tailwind CSS component library

ReaLTaiizor is a .NET WinForms control library that offers a wide range of components and is user-friendly and design-focused.

Arc Library: free, open source React components with calm motion. Copy the code or install with the shadcn CLI.

An enterprise-class UI design language and React UI library

A cross-platform and lightweight, code-first .NET GUI framework aimed at NativeAOT.

A Jetpack Compose UI framework bringing a faithful 1:1 recreation of iOS 27 Liquid Glass, animations, controls, and interactions to Android.

🧱 A suite of React components .

React Native UI library built on the Eva Design System: 30+ themeable, accessible components for iOS, Android and web. TypeScript, React 19 / RN 0.81, Eva and Material themes with runtime light/dark switching, on-demand style compilation.

Premium React components you install with shadcn. Styled by your theme, yours to change. Free and open source.

Svelte implementation of the Carbon Design System

Untitled UI React is the world’s largest collection of open-source React components built with Tailwind CSS and React Aria. Just copy, paste, and build.

React UI components of the Yamada, by the Yamada, for the Yamada built with React and Emotion.

BagUI is an open-source shadcn/ui registry with production-ready components, blocks, templates, and animations for React, Next.js, and Tailwind CSS. Copy, customize, and build faster.

Design system library by pixiv

A C++ library to create desktop applications

ranui — a Web Components UI library — plus ranuts utilities. Hand-built frontend infrastructure.

A monorepo Design System with React components.

A library with UIKit and SwiftUI components to build iOS apps faster