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 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
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
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
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
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
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
Library npm

Faker

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

15,502
MIT
Used by 60
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
89Health
Library npm

xterm.js

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

21,228
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.

15,136
MIT
Used by 57

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