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

64Health
Library npm

Chalk

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

23,315
MIT
Used by 98
45Health
Library npm

next-themes

Perfect dark mode for React and Next.js apps in two lines of code, with zero flash on load.

6,338
MIT
Used by 97
70Health
Library npm

react-day-picker

A lightweight, fully customizable date picker component for React applications.

6,852
MIT
Used by 96
97Health
Tool npm

webpack

A static module bundler that builds a dependency graph of your project's modules and packages them into optimized browser bundles

65,948
MIT
Used by 90
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
54Health
Library PyPI

HTTPX

A next-generation HTTP client for Python with sync, async, and HTTP/2 support

15,478
BSD 3
Used by 85
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
95Health
Tool npm

Storybook

The industry-standard workshop for building, documenting, and testing UI components in isolation, across every major frontend framework.

91,053
MIT
Used by 83
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
91Health
Tool PyPI

Uvicorn

A lightning-fast ASGI server for Python, built on uvloop and httptools.

10,963
BSD 3
Used by 81
56Health
Library npm

tslib

The runtime library that houses TypeScript's compiler helper functions so your emitted code stays small.

1,343
Other
Used by 81
93Health
Library npm

Mermaid

Generate flowcharts, sequence diagrams, and 20+ other diagram types from markdown-like text

90,243
MIT
Used by 80
96Health
Library PyPI

NumPy

The fundamental N-dimensional array library powering Python's scientific computing stack.

32,741
BSD 3
Used by 80
75Health
Library npm

React Resizable Panels

Resizable, draggable panel group layouts for React with keyboard accessibility and SSR support built in

5,363
MIT
Used by 80
51Health
Library npm

cors

Node.js CORS middleware for Express and Connect that sets standards-compliant headers to control cross-origin browser access.

6,194
MIT
Used by 79
55Health
Library PyPI

PyYAML

A full-featured YAML parser and emitter for Python, with C-accelerated bindings

2,942
MIT
Used by 79
92Health
Library npm

React Flow

A highly customizable React library for building node-based editors, diagrams, and interactive flow charts.

38,371
MIT
Used by 77
90Health
Framework PyPI

FastAPI

A modern, high-performance Python web framework for building APIs with automatic validation, serialization, and interactive docs.

102,333
MIT
Used by 76
83Health
Library npm

Chart.js

Simple, flexible JavaScript charting for designers and developers

67,694
MIT
Used by 73
87Health
Library npm

highlight.js

Zero-dependency JavaScript syntax highlighter with automatic language detection for over 190 languages.

24,991
BSD 3
Used by 73
65Health
Library PyPI

python-dotenv

Load environment variables from a .env file into Python's os.environ, the standard way to keep 12-factor config out of your code

8,876
BSD 3
Used by 72
53Health
Library npm

@monaco-editor/react

Drop the Monaco code editor into any React app without touching webpack, rollup, or bundler config files.

4,741
MIT
Used by 72
90Health
Tool npm

Oxlint

Rust-based JavaScript/TypeScript linter that runs 50-100x faster than ESLint, with zero configuration required.

22,741
MIT
Used by 70

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