Directory

Open Source Packages

Libraries, frameworks, tools, and SDKs used by the apps in this directory — scored the same way as the apps themselves.

5929 packages

All Packages

98Health
Library npm

React

The declarative, component-based JavaScript library for building fast, interactive user interfaces on the web and in native apps.

250,786
MIT
Used by 407
98Health
Library npm

React DOM

React's official renderer for the DOM and server — createRoot, hydrateRoot, and streaming SSR in one package.

250,786
MIT
Used by 402
92Health
Library npm

postcss

A CSS transformation engine that parses styles into an AST, letting JS plugins lint, prefix, and rewrite CSS — the foundation beneath Autoprefixer, Tailwind, and 200+ other tools.

28,977
MIT
Used by 277
92Health
Library npm

lucide-react

1,700+ tree-shakeable, customizable SVG icon components for React applications

24,747
Other
Used by 222
64Health
Library npm

React Testing Library

Simple and complete React DOM testing utilities that encourage good testing practices.

19,655
MIT
Used by 196
92Health
Library npm

TanStack Query

Hooks-based async state management for fetching, caching, and syncing server data in React.

50,368
MIT
Used by 183
74Health
Library npm

Radix UI

Unstyled, accessible React UI primitives for building your own design system.

19,339
MIT
Used by 182
66Health
Library npm

react-markdown

Safely render Markdown as React elements, no dangerouslySetInnerHTML required

15,892
MIT
Used by 164
79Health
Library npm

Motion

A hybrid JavaScript and React animation library built for 120fps gestures, springs, and layout transitions.

33,759
MIT
Used by 145
44Health
Library npm

cmdk

Fast, unstyled command menu and combobox primitives for React.

12,988
MIT
Used by 133
92Health
Library npm

React Hook Form

Performant, flexible React forms built on hooks with minimal re-renders and built-in validation.

44,864
MIT
Used by 132
91Health
Library npm

Recharts

A composable charting library for React, built on D3 and SVG.

27,594
MIT
Used by 127
78Health
Library npm

Zustand

A small, fast React state management library with a hook-based API and no boilerplate.

58,763
MIT
Used by 119
91Health
Library npm

TanStack Table

Headless, type-safe tables and datagrids for React, Vue, Solid, and more.

28,461
MIT
Used by 117
63Health
Library npm

Sonner

An opinionated, animated toast notification component for React with a tiny imperative API.

13,016
MIT
Used by 117
77Health
Library npm

user-event

Simulates the full sequence of real browser events so Testing Library tests behave the way an actual user does.

2,330
MIT
Used by 116
72Health
Library Cargo

serde_json

The de facto standard JSON library for Rust, built on the Serde serialization framework

5,638
Apache 2.0
Used by 113
81Health
Library PyPI

Requests

The elegant, human-friendly HTTP library that made Python's most-used API for talking to the web.

54,353
Apache 2.0
Used by 112
94Health
Library npm

Marked

A fast, low-level Markdown compiler that parses CommonMark and GFM into HTML in Node.js, browsers, or the CLI.

37,214
MIT
Used by 112
76Health
Library Cargo

serde

A generic framework for serializing and deserializing Rust data structures efficiently and safely.

10,838
Other
Used by 109
81Health
Library npm

dnd-kit

A lightweight, extensible React library for building accessible drag-and-drop interfaces.

17,679
MIT
Used by 107
92Health
Library npm

AI SDK

Provider-agnostic TypeScript toolkit for building AI apps and agents with any LLM.

26,955
Apache 2.0
Used by 105
93Health
Library PyPI

Pydantic

Data validation and settings management using Python type hints, backed by a Rust core.

28,891
MIT
Used by 104
82Health
Library npm

js-yaml

A fast, complete YAML 1.2 and 1.1 parser and serializer for JavaScript.

6,634
MIT
Used by 101

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