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

92Health
Framework npm

Playwright

Cross-browser end-to-end web testing and browser automation with a single API for Chromium, Firefox, and WebKit.

96,127
Apache 2.0
Used by 228
86Health
Framework npm

Express

The fast, unopinionated, minimalist web framework for Node.js

69,454
MIT
Used by 158
96Health
Framework PyPI

pytest

The Python testing framework that makes writing small tests easy and scales to complex functional test suites.

14,506
MIT
Used by 100
63Health
Framework npm

Commander.js

The complete, battle-tested framework for building Node.js command-line interfaces.

28,391
MIT
Used by 94
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
97Health
Framework npm

Electron

Build cross-platform desktop apps with JavaScript, HTML, and CSS on Chromium and Node.js

123,052
MIT
Used by 68
55Health
Framework Go

Cobra

The commander library that powers Kubernetes, Hugo, and GitHub CLI's command-line interfaces.

44,603
Apache 2.0
Used by 62
94Health
Framework npm

TanStack Router

A fully type-safe React router with built-in data loading, caching, and URL search-param validation.

15,081
MIT
Used by 56
79Health
Framework npm

yargs

The modern, pirate-themed command-line argument parser and command framework for Node.js

11,504
MIT
Used by 42
95Health
Framework PyPI

aiohttp

Asynchronous HTTP client and server framework for Python's asyncio, covering both API calls and building web/WebSocket services.

16,548
Apache 2.0
Used by 40
95Health
Framework PyPI

Transformers

State-of-the-art pretrained models for text, vision, audio, and multimodal inference and training.

165,971
Apache 2.0
Used by 37
93Health
Framework npm

Docusaurus

React-based static site generator for building fast, maintainable documentation websites.

66,246
MIT
Used by 36
93Health
Framework npm

NestJS

A progressive Node.js framework for building efficient, scalable, and maintainable server-side applications in TypeScript.

76,663
MIT
Used by 27
83Health
Framework npm

Expo

Open-source framework for building universal native apps with React that run on Android, iOS, and the web.

52,237
MIT
Used by 27
90Health
Framework PyPI

Typer

Typer is a Python library for building CLI applications, using type hints to generate arguments, options, validation, help text, and shell completion automatically.

19,983
MIT
Used by 26
98Health
Framework npm

Bootstrap

The world's most popular front-end framework for building responsive, mobile-first sites

174,791
MIT
Used by 25
92Health
Framework PyPI

LangChain

The most widely adopted Python framework for building LLM-powered agents and applications

146,323
MIT
Used by 21
93Health
Framework PyPI

Starlette

A lightweight ASGI framework/toolkit for building async web services and apps in Python

12,618
BSD 3
Used by 21
83Health
Framework PyPI

Flask

A lightweight WSGI web framework for Python that scales from a single file to complex applications.

74,737
BSD 3
Used by 20
92Health
Framework PyPI

LangGraph

A low-level orchestration framework for building stateful, multi-actor LLM agents as graphs

41,635
MIT
Used by 18
98Health
Framework npm

@angular/core

The core runtime of Angular: components, dependency injection, change detection, and signals for building web, mobile, and desktop apps.

101,007
MIT
Used by 16
89Health
Framework npm

Slate

Completely customizable framework for building rich text editors

31,748
MIT
Used by 16
87Health
Framework PyPI

Django

The high-level Python web framework that turns database models into secure, working web applications in record time.

91,063
BSD 3
Used by 15
92Health
Framework PyPI

django-rest-framework

The most widely-used toolkit for building Web APIs on top of Django, with serializers, viewsets, and a built-in browsable API.

30,179
BSD 3
Used by 15

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