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.

250,443
MIT
Used by 404
98Health
Library npm

React DOM

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

250,443
MIT
Used by 399
74Health
Library npm

dotenv

Loads environment variables from a .env file into process.env for Node.js apps.

20,536
Other
Used by 227
68Health
Library npm

date-fns

Modern JavaScript date utility library with 200+ pure, immutable functions

36,648
MIT
Used by 202
93Health
Library npm

jsdom

A pure-JavaScript implementation of the WHATWG DOM and HTML standards for Node.js.

21,681
MIT
Used by 199
65Health
Library npm

React Testing Library

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

19,651
MIT
Used by 195
76Health
Library npm

Lodash

A modern JavaScript utility library delivering modularity, performance, and extras for arrays, objects, and functions.

61,278
MIT
Used by 194
95Health
Library npm

Axios

Promise-based HTTP client for the browser and Node.js with interceptors, automatic transforms, and cancellation

109,212
MIT
Used by 190
66Health
Library npm

jest-dom

Custom Jest matchers for asserting on the state of the DOM in your tests.

4,597
MIT
Used by 165
95Health
Library npm

@babel/core

The core JavaScript compiler that transforms next-generation syntax into code every browser and runtime can understand.

43,996
MIT
Used by 163
40Health
Library npm

remark-gfm

Add GitHub Flavored Markdown support to remark for tables, task lists, footnotes, and strikethrough.

1,246
MIT
Used by 149
90Health
Library npm

DOMPurify

DOM-only, uber-tolerant XSS sanitizer for HTML, MathML, and SVG that runs in the browser and on the server.

17,387
Apache 2.0
Used by 135
91Health
Library npm

Recharts

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

27,555
MIT
Used by 127
93Health
Library npm

TanStack Table

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

28,426
MIT
Used by 116
83Health
Library npm

ws

A simple, blazing-fast, thoroughly tested WebSocket client and server library for Node.js.

22,804
MIT
Used by 116
79Health
Library npm

user-event

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

2,326
MIT
Used by 116
89Health
Library npm

sharp

High-performance Node.js image processing powered by libvips, built for fast resizing and format conversion.

32,677
Apache 2.0
Used by 109
85Health
Library npm

i18next

The internationalization framework for JavaScript, with zero runtime dependencies and a pluggable ecosystem for every environment.

8,633
MIT
Used by 109
92Health
Library npm

AI SDK

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

26,733
Apache 2.0
Used by 105
64Health
Library npm

Chalk

The most popular Node.js library for styling terminal string output with ANSI colors.

23,315
MIT
Used by 98
69Health
Library npm

DOM Testing Library

Simple, framework-agnostic DOM query utilities that test your UI the way real users interact with it.

3,332
MIT
Used by 87
56Health
Library npm

fs-extra

Drop-in replacement for Node's fs module adding copy, remove, mkdirs, and JSON helpers with native promise support.

9,589
MIT
Used by 84
92Health
Library npm

Tiptap Core

Headless, framework-agnostic rich text editor toolkit built on ProseMirror

38,382
MIT
Used by 82
91Health
Library npm

TanStack Virtual (React)

Headless React hook for virtualizing massive lists, grids, and tables at 60FPS.

7,107
MIT
Used by 82

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