A minimal React state management library from RisingStack built on transparent reactive proxies. You wrap state objects with `store()` and components with `view()`, then mutate state with plain JavaScript and components re-render automatically based on which store properties they read.

mobx.dart is an open-source Dart project in the state management space with 2.5k GitHub stars. The repository is actively maintained, with recent commits.

ai-sdk-tools is an open-source TypeScript project in the agent frameworks space with 2.1k GitHub stars. The repository has seen commits within the last year.

Data Client is a TypeScript data-fetching and normalized caching library for React (and Vue, React Native, Next.js, Expo) that uses declarative, schema-driven resource definitions to bind dynamic data—REST, GraphQL, WebSockets/SSE—to components with one-line hooks and zero manual cache updater functions.

Material UI is a comprehensive React component library implementing Google's Material Design, providing a large set of ready-made, customizable, accessible UI components and a powerful theming/styling system.

Magic UI is a collection of animated React components and effects built with Tailwind CSS and Framer Motion, aimed at design engineers who want polished landing-page and marketing-site visuals. Components are copy-pasted into your project (shadcn/ui-style) rather than installed as a runtime dependency.

Radix Primitives is a low-level, unstyled React component library that provides accessible, customizable building blocks (dialogs, dropdowns, tooltips, etc.) for constructing design systems and web apps. It handles the hard parts—accessibility, keyboard interaction, focus management—while leaving styling entirely up to you.

Naive UI is a Vue 3 component library written entirely in TypeScript, offering 90+ tree-shakable components with a JS-based, type-safe theming system that requires no separate CSS imports or build-loader configuration.

Riot.js is a tiny, component-based UI library that brings a custom-tag authoring model to the browser, letting you write HTML-centric components with inline scripts, lifecycle hooks, and one-way data flow without a virtual DOM.

PrimeVue is a comprehensive open-source UI component library for Vue 3, offering 90+ ready-made components with theming, accessibility support, and first-class Nuxt integration.

PrimeNG is a comprehensive open-source UI component library for Angular, offering 80+ ready-made components such as data tables, forms, overlays, charts, and menus, along with theming support.

Flowbite is an open-source UI component library built on top of Tailwind CSS, providing pre-styled interactive elements (modals, dropdowns, navbars, tooltips, etc.) that can be wired up via HTML data attributes or controlled programmatically through a JavaScript/TypeScript API.

An enterprise-focused Angular UI component library implementing the Ant Design system, providing 70+ TypeScript components with theming, i18n, SSR, and zoneless/OnPush support.

Radix Themes is a pre-styled, themeable React component library built on top of Radix UI's accessible primitives, offering a complete design system with ready-to-use components, tokens, and styling controls for rapid app development.

NES.css is a pure-CSS framework that styles UI elements—buttons, inputs, containers, icons, and dialogs—with a retro 8-bit, NES-inspired pixel aesthetic. It ships only components with no JavaScript dependency, leaving layout up to the developer.

PrimeReact is a comprehensive UI component library for React, offering 90+ pre-built, themeable components ranging from form inputs and data tables to charts and overlays. It supports both styled (pre-skinned themes like Material and Bootstrap) and unstyled modes for full customization.

React95 is a React component library that recreates the Windows 95 user interface aesthetic with modern, themeable components built on styled-components. It provides classic widgets like menus, windows, buttons, and separators for building retro-styled web apps.

A comprehensive UI toolset and component library for React Native by Wix, offering pre-built components plus a design-system foundation layer (colors, typography, spacings) and a modifier-based styling syntax for rapidly composing theme-consistent screens.

Reka UI (formerly Radix Vue) is an unstyled, accessible component library for Vue, providing low-level UI primitives that handle behavior, keyboard interaction, and ARIA semantics while leaving styling fully up to the developer.

Arco Design is a comprehensive React UI component library (60+ components) built on ByteDance's Arco Design system, with strong TypeScript support, extensive theming via design tokens, and a surrounding ecosystem for themes, materials, and icons.