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

97Health
Tool npm

TypeScript

A strongly typed superset of JavaScript that compiles to clean, portable JavaScript.

111,245
Apache 2.0
Used by 503
95Health
Tool npm

ESLint

The pluggable JavaScript and TypeScript linter that finds and fixes code problems through a fully customizable, plugin-based rule engine.

27,518
MIT
Used by 368
91Health
Tool npm

prettier

An opinionated code formatter that enforces consistent style across every language your project speaks.

52,316
MIT
Used by 310
94Health
Tool npm

typescript-eslint

The official meta-package bundling the TypeScript ESLint parser, plugin, and rule presets behind a single typed config() helper.

16,401
MIT
Used by 260
92Health
Framework npm

Playwright

Cross-browser end-to-end web testing and browser automation with a single API for Chromium, Firefox, and WebKit.

96,772
Apache 2.0
Used by 229
93Health
Tool npm

@vitejs/plugin-react

The official Vite plugin for React with Babel-powered Fast Refresh and JSX transforms

1,167
MIT
Used by 211
68Health
Tool npm

eslint-config-prettier

Disables ESLint stylistic rules that conflict with Prettier, so the two tools never fight over formatting.

5,893
MIT
Used by 169
95Health
Framework npm

React Router

A multi-strategy router for React, from a lightweight library to a full SSR framework.

56,590
MIT
Used by 167
85Health
Framework npm

Express

The fast, unopinionated, minimalist web framework for Node.js

69,493
MIT
Used by 158
96Health
Framework npm

Next.js

The React framework for production: file-based routing, server rendering, and Rust-powered builds.

142,803
MIT
Used by 154
81Health
Tool npm

esbuild

An extremely fast JavaScript and CSS bundler and minifier written in Go.

40,071
MIT
Used by 139
61Health
Tool npm

eslint-plugin-react

React-specific linting rules for ESLint that catch JSX bugs, enforce Hooks conventions, and keep prop usage consistent.

9,293
MIT
Used by 122
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
96Health
Framework PyPI

pytest

The Python testing framework that makes writing small tests easy and scales to complex functional test suites.

14,543
MIT
Used by 100
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
91Health
Tool PyPI

Uvicorn

A lightning-fast ASGI server for Python, built on uvloop and httptools.

10,993
BSD 3
Used by 83
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
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
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
56Health
Tool npm

eslint-plugin-jsx-a11y

Static ESLint rules that catch JSX accessibility issues before code ships.

3,621
MIT
Used by 65
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
90Health
Tool npm

SWC

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

34,208
Apache 2.0
Used by 56
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.

49,811
MIT
Used by 46

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