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

95Health
Library PyPI

NumPy

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

32,864
BSD 3
Used by 82
55Health
Library npm

tslib

The runtime library that houses TypeScript's compiler helper functions so your emitted code stays small.

1,343
Other
Used by 81
92Health
Library npm

Mermaid

Generate flowcharts, sequence diagrams, and 20+ other diagram types from markdown-like text

90,450
MIT
Used by 80
53Health
Library PyPI

PyYAML

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

2,950
MIT
Used by 80
50Health
Library npm

cors

Node.js CORS middleware for Express and Connect that sets standards-compliant headers to control cross-origin browser access.

6,195
MIT
Used by 79
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
91Health
Library npm

React Flow

A highly customizable React library for building node-based editors, diagrams, and interactive flow charts.

38,512
MIT
Used by 78
58Health
Library npm

node-fetch

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

8,855
MIT
Used by 74
81Health
Library npm

Chart.js

Simple, flexible JavaScript charting for designers and developers

67,719
MIT
Used by 73
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
82Health
Library Cargo

reqwest

An ergonomic, batteries-included HTTP client for Rust, with async and blocking APIs.

11,845
Other
Used by 72
90Health
Tool npm

Oxlint

Rust-based JavaScript/TypeScript linter that runs 50-100x faster than ESLint, with zero configuration required.

22,902
MIT
Used by 70
63Health
Library npm

diff

A battle-tested JavaScript library for computing and applying text diffs at the character, word, line, sentence, CSS, or JSON level.

9,210
BSD 3
Used by 70
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
68Health
Library Cargo

tempfile

A secure, cross-platform Rust library for temporary files and directories that clean up automatically on drop.

1,468
Other
Used by 69
85Health
Library npm

Floating UI

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

32,753
MIT
Used by 68
67Health
Library npm

JSZip

Create, read, and edit ZIP files directly in JavaScript, in the browser or Node.js.

10,386
Other
Used by 66
66Health
Library Cargo

base64

Correct, fast, and configurable base64 encoding and decoding for Rust, with pluggable alphabets and padding.

738
Apache 2.0
Used by 66
69Health
Library npm

Fuse.js

Lightweight, zero-dependency fuzzy-search library for JavaScript and TypeScript, in the browser or on the server.

20,491
Apache 2.0
Used by 65
92Health
Library npm

KaTeX

Fast, self-contained JavaScript library for print-quality LaTeX math rendering on the web.

20,405
MIT
Used by 65
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
98Health
Library PyPI

pandas

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

49,851
BSD 3
Used by 61

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