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

84Health
Library npm

ws

A simple, blazing-fast, thoroughly tested WebSocket client and server library for Node.js.

22,807
MIT
Used by 116
78Health
Tool npm

eslint-plugin-import

ESLint rules that validate ES module import/export syntax and catch broken paths before they hit your build.

5,947
MIT
Used by 116
77Health
Library npm

user-event

Simulates the full sequence of real browser events so Testing Library tests behave the way an actual user does.

2,330
MIT
Used by 116
72Health
Library Cargo

serde_json

The de facto standard JSON library for Rust, built on the Serde serialization framework

5,638
Apache 2.0
Used by 113
94Health
Library npm

Marked

A fast, low-level Markdown compiler that parses CommonMark and GFM into HTML in Node.js, browsers, or the CLI.

37,214
MIT
Used by 112
95Health
SDK npm

Sentry JavaScript (@sentry/browser)

The official Sentry SDK for capturing errors, performance traces, and session replays in browser JavaScript apps.

8,745
MIT
Used by 110
82Health
Library npm

i18next

The internationalization framework for JavaScript, with zero runtime dependencies and a pluggable ecosystem for every environment.

8,637
MIT
Used by 110
90Health
Library npm

sharp

High-performance Node.js image processing powered by libvips, built for fast resizing and format conversion.

32,726
Apache 2.0
Used by 109
76Health
Library Cargo

serde

A generic framework for serializing and deserializing Rust data structures efficiently and safely.

10,838
Other
Used by 109
92Health
Library npm

AI SDK

Provider-agnostic TypeScript toolkit for building AI apps and agents with any LLM.

26,955
Apache 2.0
Used by 105
82Health
Library npm

js-yaml

A fast, complete YAML 1.2 and 1.1 parser and serializer for JavaScript.

6,634
MIT
Used by 101
88Health
Library npm

yaml

A definitive TypeScript parser and stringifier for YAML, supporting 1.1 and 1.2 with comment and CST access.

1,692
Other
Used by 99
72Health
Library npm

Chalk

The most popular Node.js library for styling terminal string output with ANSI colors.

23,319
MIT
Used by 98
95Health
Framework Cargo

Tokio

The async runtime powering most of Rust's networked, concurrent, and I/O-bound applications.

33,257
MIT
Used by 96
62Health
Framework npm

Commander.js

The complete, battle-tested framework for building Node.js command-line interfaces.

28,412
MIT
Used by 94
95Health
Tool npm

Storybook

The industry-standard workshop for building, documenting, and testing UI components in isolation, across every major frontend framework.

91,163
MIT
Used by 90
97Health
Tool npm

webpack

A static module bundler that builds a dependency graph of your project's modules and packages them into optimized browser bundles

65,963
MIT
Used by 90
67Health
Library npm

DOM Testing Library

Simple, framework-agnostic DOM query utilities that test your UI the way real users interact with it.

3,335
MIT
Used by 87
64Health
Library npm

fs-extra

Drop-in replacement for Node's fs module adding copy, remove, mkdirs, and JSON helpers with native promise support.

9,590
MIT
Used by 84
90Health
Library npm

TanStack Virtual (React)

Headless React hook for virtualizing massive lists, grids, and tables at 60FPS.

7,123
MIT
Used by 83
91Health
Library npm

Tiptap Core

Headless, framework-agnostic rich text editor toolkit built on ProseMirror

38,558
MIT
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
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

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