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

63Health
Library npm

i18next-browser-languageDetector

Detects a visitor's language from cookies, storage, the URL, or the browser itself and wires it straight into i18next.

972
MIT
Used by 53
89Health
Library npm

Immer

Create your next immutable state by mutating the current one.

28,992
MIT
Used by 52
79Health
Library npm

markdown-it

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

21,999
MIT
Used by 52
90Health
Library npm

React Email

High-quality, unstyled React components for building responsive HTML emails

19,868
MIT
Used by 52
49Health
Library npm

cookie-parser

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

2,032
MIT
Used by 52
49Health
Library npm

tar

The battle-tested tar archive library that powers npm itself, with hardened extraction against path-traversal and symlink attacks.

924
Other
Used by 52
82Health
Library npm

Embla Carousel React

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

8,458
MIT
Used by 51
77Health
Library Cargo

tracing

Structured, application-level diagnostics for async Rust programs, built around scoped spans and events.

6,940
MIT
Used by 51
85Health
Library npm

Streamdown

A drop-in react-markdown replacement built for AI-powered streaming interfaces.

5,721
Apache 2.0
Used by 51
67Health
Tool npm

babel-loader

Babel loader for webpack (and Rspack) that transpiles modern JavaScript with filesystem caching and source map support.

4,836
MIT
Used by 51
55Health
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.

25,526
MIT
Used by 50
51Health
Library npm

Winston

A battle-tested Node.js logging library with pluggable transports, custom formats, and multiple log levels.

24,527
MIT
Used by 50
87Health
Library PyPI

Click

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

17,800
BSD 3
Used by 50
67Health
Library Cargo

anyhow

Flexible, idiomatic error handling for Rust applications with a single concrete error type.

6,685
Apache 2.0
Used by 50
95Health
Framework npm

Vue Router

The official client-side router for Vue.js, powering nested routes, navigation guards, and single-page app navigation.

4,700
MIT
Used by 50
74Health
Library npm

@rollup/plugin-alias

Rollup plugin for defining and resolving import aliases, swapping brittle relative paths for clean, refactor-safe module names.

3,761
MIT
Used by 50
48Health
Tool npm

eslint-import-resolver-typescript

A TypeScript-aware module resolver that plugs into eslint-plugin-import(-x) so ESLint can correctly follow .ts/.tsx imports, tsconfig paths, and package export maps.

829
Other
Used by 50
54Health
Library npm

Headless UI

Unstyled, fully accessible UI components for React and Vue, built for Tailwind CSS

28,797
MIT
Used by 49
74Health
Library npm

qs

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

8,948
BSD 3
Used by 49
48Health
Library npm

Vaul

An unstyled, physics-based drawer component for React, built on Radix UI's Dialog primitive.

8,649
MIT
Used by 49
78Health
Library npm

react-error-boundary

Reusable React error boundary component that catches rendering errors and shows a fallback UI.

7,994
MIT
Used by 49
52Health
Library npm

lru-cache

A fast, type-safe, zero-dependency LRU cache for JavaScript and TypeScript

5,918
Other
Used by 49
90Health
Tool PyPI

pytest-asyncio

The pytest plugin that lets you write and run async/await test functions and fixtures directly.

1,666
Apache 2.0
Used by 49

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