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

94Health
Tool npm

Vite

Next-generation frontend build tool with an instant dev server, lightning-fast HMR, and optimized production builds.

82,823
MIT
Used by 324
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.

28,972
MIT
Used by 277
86Health
Framework npm

Express

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

69,454
MIT
Used by 158
96Health
Framework npm

Next.js

The React framework for production: file-based routing, server rendering, and Rust-powered builds.

142,310
MIT
Used by 154
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
92Health
Library npm

undici

A fast, spec-compliant HTTP/1.1 client for Node.js, built from scratch with zero runtime dependencies

7,695
MIT
Used by 70
90Health
Framework npm

Hono

A small, ultrafast web framework built on Web Standards that runs identically everywhere.

32,186
MIT
Used by 60
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
93Health
Library PyPI

urllib3

A powerful, user-friendly HTTP client for Python with thread-safe connection pooling, TLS verification, and retry handling.

4,058
MIT
Used by 48
68Health
Library npm

proxy-agent

Maps HTTP, HTTPS, SOCKS, and PAC proxy protocols to the correct Node.js http.Agent implementation automatically.

1,161
MIT
Used by 47
90Health
Library npm

Prisma Client

Auto-generated, type-safe database client for Node.js and TypeScript.

47,610
Apache 2.0
Used by 46
95Health
Library npm

Socket.IO

Bidirectional, low-latency, event-based realtime communication for Node.js and the browser.

63,200
MIT
Used by 39
92Health
SDK npm

@clickhouse/client

The official TypeScript client for connecting Node.js applications to ClickHouse over HTTP.

331
Apache 2.0
Used by 38
93Health
Library Composer

Guzzle

An extensible PHP HTTP client for sending requests and integrating with web services

23,455
MIT
Used by 31
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
98Health
Framework npm

Bootstrap

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

174,791
MIT
Used by 25
94Health
Library npm

Ant Design

An enterprise-class React UI library with 80+ high-quality, TypeScript-typed components and powerful theming.

99,507
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

37,137
MIT
Used by 25
71Health
Framework Go

Gin

A high-performance HTTP web framework for Go, built on a zero-allocation radix-tree router with an Express.js-style API.

89,216
MIT
Used by 22
94Health
Framework npm

SvelteKit

The official application framework for Svelte, providing filesystem routing, server rendering, and adapters for any deployment target.

20,807
MIT
Used by 22
92Health
Framework PyPI

LangChain

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

146,323
MIT
Used by 21
98Health
Framework Composer

Laravel

The expressive, elegant PHP framework for building modern web applications

34,910
MIT
Used by 21
84Health
Library npm

http-proxy-middleware

The one-liner Node.js proxy middleware for connect, express, next.js, hono, and more.

11,126
MIT
Used by 20

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