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

85Health
Library npm

Floating UI

React hooks and components for building accessible, perfectly positioned tooltips, popovers, and dropdowns.

32,753
MIT
Used by 68
56Health
Tool npm

eslint-plugin-jsx-a11y

Static ESLint rules that catch JSX accessibility issues before code ships.

3,621
MIT
Used by 65
92Health
Library PyPI

Pillow

The friendly PIL fork that adds image processing capabilities to Python

13,856
Other
Used by 62
63Health
Library Cargo

url

A WHATWG-standard-compliant URL parser and manipulation library for Rust.

1,575
Apache 2.0
Used by 62
98Health
Library PyPI

pandas

The Python DataFrame library for fast, flexible, and expressive data analysis and manipulation.

49,851
BSD 3
Used by 61
79Health
Library npm

PapaParse

The fastest in-browser CSV parser for JavaScript, with streaming, Web Workers, and zero dependencies

13,576
MIT
Used by 61
91Health
SDK PyPI

boto3

The official AWS SDK for Python — call every Amazon Web Services API from your code.

9,909
Apache 2.0
Used by 60
97Health
SDK PyPI

OpenAI Python SDK

The official Python library for the OpenAI REST API, generated from OpenAI's OpenAPI spec with typed sync and async clients.

31,709
Apache 2.0
Used by 59
90Health
Tool npm

SWC

Rust-based JavaScript/TypeScript compiler, a drop-in super-fast alternative to Babel

34,208
Apache 2.0
Used by 56
90Health
Library Cargo

Clap

The most widely used command-line argument parser for Rust, with both derive and builder APIs.

16,725
Other
Used by 56
84Health
Library PyPI

cryptography

The standard cryptographic library for Python, pairing safe high-level recipes with low-level primitives backed by Rust and OpenSSL.

7,786
Other
Used by 54
78Health
Library npm

markdown-it

A fast, pluggable CommonMark-compliant Markdown parser and renderer for JavaScript, safe by default.

21,945
MIT
Used by 52
90Health
Library npm

React Email

High-quality, unstyled React components for building responsive HTML emails

19,788
MIT
Used by 51
88Health
Library PyPI

Click

A composable Python toolkit for building command line interfaces with minimal boilerplate.

17,770
BSD 3
Used by 50
93Health
Library PyPI

urllib3

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

4,064
MIT
Used by 48
73Health
Library PyPI

python-dateutil

Powerful extensions to Python's datetime module for parsing, deltas, recurrence, and timezones.

2,637
Other
Used by 48
57Health
Library PyPI

rich

A Python library for rendering rich text, tables, progress bars, and syntax-highlighted code in the terminal.

57,443
MIT
Used by 47
90Health
Tool PyPI

Ruff

An extremely fast Python linter and code formatter, written in Rust, built as a drop-in replacement for Flake8, Black, isort, and dozens of plugins.

49,811
MIT
Used by 46
90Health
Library npm

Cheerio

The fast, flexible library for parsing and manipulating HTML and XML with a familiar jQuery-style API.

30,505
MIT
Used by 45
53Health
Library PyPI

Jinja

A fast, expressive, and extensible templating engine for Python.

11,789
BSD 3
Used by 45
86Health
Library PyPI

PyJWT

A Python implementation of RFC 7519 for encoding, decoding, and verifying JSON Web Tokens.

5,706
MIT
Used by 44
48Health
Library npm

unified

Parse, inspect, transform, and serialize content through syntax-tree plugins.

5,036
MIT
Used by 44
93Health
Library PyPI

SQLAlchemy

The Python SQL toolkit and Object Relational Mapper that gives developers the full power and flexibility of SQL.

12,189
MIT
Used by 43
75Health
Framework npm

yargs

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

11,504
MIT
Used by 42

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