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

55Health
Library PyPI

PyYAML

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

2,942
MIT
Used by 79
92Health
Library npm

React Flow

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

38,371
MIT
Used by 77
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
83Health
Library npm

Chart.js

Simple, flexible JavaScript charting for designers and developers

67,694
MIT
Used by 73
87Health
Library npm

highlight.js

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

24,991
BSD 3
Used by 73
65Health
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

8,876
BSD 3
Used by 72
90Health
Tool npm

Oxlint

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

22,741
MIT
Used by 70
60Health
Library npm

diff

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

9,207
BSD 3
Used by 70
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
97Health
Framework npm

Electron

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

123,052
MIT
Used by 68
71Health
Library npm

Fuse.js

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

20,479
Apache 2.0
Used by 65
92Health
Library npm

KaTeX

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

20,387
MIT
Used by 65
69Health
Library npm

JSZip

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

10,383
Other
Used by 65
55Health
Framework Go

Cobra

The commander library that powers Kubernetes, Hugo, and GitHub CLI's command-line interfaces.

44,603
Apache 2.0
Used by 62
98Health
Library PyPI

pandas

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

49,732
BSD 3
Used by 61
81Health
Library npm

PapaParse

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

13,568
MIT
Used by 61
91Health
Library npm

Faker

Generate massive amounts of realistic fake data for testing, seeding, and mocking in JavaScript and TypeScript.

15,486
MIT
Used by 60
92Health
Library PyPI

Pillow

The friendly PIL fork that adds image processing capabilities to Python

13,812
Other
Used by 60
91Health
SDK PyPI

boto3

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

9,900
Apache 2.0
Used by 59
96Health
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.

31,622
Apache 2.0
Used by 57
90Health
Library npm

xterm.js

A fast, self-contained TypeScript library for embedding fully-featured terminals in the browser.

21,173
MIT
Used by 57
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
90Health
Tool npm

SWC

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

34,191
Apache 2.0
Used by 55
82Health
Library npm

RxJS

The standard library for composing asynchronous and event-based programs using observable sequences

31,698
Apache 2.0
Used by 53

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