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

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
90Health
Tool npm

Stylelint

An extensible CSS linter that catches errors and enforces consistent styling conventions.

11,519
MIT
Used by 58
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
84Health
Library PyPI

cryptography

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

7,765
Other
Used by 53
79Health
Library npm

markdown-it

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

21,901
MIT
Used by 52
51Health
Library npm

cookie-parser

Express middleware that parses HTTP Cookie headers into req.cookies, with support for signed and JSON-encoded cookie values.

2,030
MIT
Used by 52
83Health
Library npm

Embla Carousel React

A lightweight, dependency-free React hook for building fluid, touch-precise carousels and sliders.

8,414
MIT
Used by 51
56Health
Library npm

bcrypt.js

A zero-dependency, pure JavaScript implementation of bcrypt for hashing and verifying passwords in Node.js and the browser.

3,797
BSD 3
Used by 51
91Health
Library npm

core-js

Modular standard library and polyfills for JavaScript, from ECMAScript features to proposals and web standards.

25,531
MIT
Used by 50
88Health
Library PyPI

Click

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

17,664
BSD 3
Used by 50
75Health
Library npm

qs

A battle-tested querystring parser and serializer for Node.js with nested object support and built-in security limits.

8,940
BSD 3
Used by 49
66Health
Library npm

remark

A plugin-powered markdown processor that parses, transforms, and serializes markdown on top of unified.

8,995
MIT
Used by 48
93Health
Library PyPI

urllib3

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

4,058
MIT
Used by 48
53Health
Library PyPI

python-dateutil

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

2,634
Other
Used by 48
62Health
Library PyPI

rich

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

57,363
MIT
Used by 46
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.

49,630
MIT
Used by 46
90Health
Library npm

Prisma Client

Auto-generated, type-safe database client for Node.js and TypeScript.

47,610
Apache 2.0
Used by 46
57Health
Library npm

reflect-metadata

A polyfill for the Metadata Reflection API that powers decorator metadata in TypeScript and JavaScript.

3,360
Apache 2.0
Used by 46

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