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

78Health
Library npm

date-fns

Modern JavaScript date utility library with 200+ pure, immutable functions

36,647
MIT
Used by 202
94Health
Library npm

Axios

Promise-based HTTP client for the browser and Node.js with interceptors, automatic transforms, and cancellation

109,216
MIT
Used by 190
78Health
Library npm

Zustand

A small, fast React state management library with a hook-based API and no boilerplate.

58,763
MIT
Used by 119
81Health
Library PyPI

Requests

The elegant, human-friendly HTTP library that made Python's most-used API for talking to the web.

54,353
Apache 2.0
Used by 112
94Health
Library npm

Marked

A fast, low-level Markdown compiler that parses CommonMark and GFM into HTML in Node.js, browsers, or the CLI.

37,214
MIT
Used by 112
93Health
Library PyPI

Pydantic

Data validation and settings management using Python type hints, backed by a Rust core.

28,891
MIT
Used by 104
85Health
Library npm

@hookform/resolvers

Official React Hook Form adapters that plug 20+ schema-validation libraries — Zod, Yup, Joi, Valibot, ArkType and more — straight into useForm's resolver.

2,263
MIT
Used by 93
56Health
Library PyPI

HTTPX

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

15,517
BSD 3
Used by 86
95Health
Library PyPI

NumPy

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

32,864
BSD 3
Used by 82
53Health
Library PyPI

PyYAML

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

2,950
MIT
Used by 80
58Health
Library npm

node-fetch

A lightweight, spec-compliant implementation of the browser Fetch API for Node.js

8,855
MIT
Used by 74
86Health
Library npm

highlight.js

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

24,999
BSD 3
Used by 73
63Health
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

8,883
BSD 3
Used by 73
85Health
Library npm

Floating UI

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

32,753
MIT
Used by 68
92Health
Library PyPI

Pillow

The friendly PIL fork that adds image processing capabilities to Python

13,856
Other
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
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
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
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

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