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.

96,772
Apache 2.0
Used by 229
85Health
Framework npm

Express

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

69,493
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.

14,543
MIT
Used by 100
91Health
Framework PyPI

FastAPI

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

102,676
MIT
Used by 78
97Health
Framework npm

Electron

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

123,289
MIT
Used by 69
94Health
Framework npm

TanStack Router

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

15,136
MIT
Used by 57
95Health
Framework PyPI

aiohttp

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

16,561
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.

166,736
Apache 2.0
Used by 38
92Health
Framework npm

Docusaurus

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

66,349
MIT
Used by 36
81Health
Framework PyPI

Flask

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

74,802
BSD 3
Used by 28
92Health
Framework npm

NestJS

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

76,743
MIT
Used by 27
88Health
Framework npm

Expo

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

52,467
MIT
Used by 27
89Health
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.

20,033
MIT
Used by 26
97Health
Framework npm

Bootstrap

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

174,919
MIT
Used by 25
91Health
Framework npm

Fastify

A fast and low-overhead web framework for Node.js, built around schema-based validation and a plugin architecture

37,205
MIT
Used by 25
87Health
Framework PyPI

Django

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

91,218
BSD 3
Used by 24
92Health
Framework PyPI

LangChain

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

147,170
MIT
Used by 21
98Health
Framework Composer

Laravel

The expressive, elegant PHP framework for building modern web applications

34,931
MIT
Used by 21
94Health
Framework PyPI

Starlette

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

12,639
BSD 3
Used by 21
92Health
Framework PyPI

LangGraph

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

42,375
MIT
Used by 18
92Health
Framework Go

urfave/cli

A declarative, dependency-free Go package for building fast, friendly command-line tools.

24,260
MIT
Used by 17
98Health
Framework npm

@angular/core

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

101,037
MIT
Used by 16
89Health
Framework npm

Slate

Completely customizable framework for building rich text editors

31,754
MIT
Used by 16
91Health
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.

30,191
BSD 3
Used by 15

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