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
Tool npm

prettier

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

52,263
MIT
Used by 310
92Health
Library npm

postcss

A CSS transformation engine that parses styles into an AST, letting JS plugins lint, prefix, and rewrite CSS — the foundation beneath Autoprefixer, Tailwind, and 200+ other tools.

28,972
MIT
Used by 277
94Health
Tool npm

typescript-eslint

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

16,391
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.

96,127
Apache 2.0
Used by 228
65Health
Library npm

React Testing Library

Simple and complete React DOM testing utilities that encourage good testing practices.

19,651
MIT
Used by 195
66Health
Library npm

jest-dom

Custom Jest matchers for asserting on the state of the DOM in your tests.

4,597
MIT
Used by 165
94Health
Tool npm

jest

Delightful JavaScript testing with zero-config setup, snapshots, mocking, and coverage

45,457
MIT
Used by 149
89Health
Tool npm

lint-staged

Run linters and formatters only against the files staged in git, so a slow full-project lint never blocks a commit.

14,731
MIT
Used by 120
79Health
Library npm

user-event

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

2,326
MIT
Used by 116
95Health
Library npm

Marked

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

37,141
MIT
Used by 112
75Health
Library Cargo

serde_json

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

5,636
Apache 2.0
Used by 111
73Health
Library Go

testify

The essential Go toolkit for assertions, mocks, and structured test suites.

26,203
MIT
Used by 102
82Health
Library npm

js-yaml

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

6,630
MIT
Used by 101
96Health
Framework PyPI

pytest

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

14,506
MIT
Used by 100
90Health
Library npm

yaml

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

1,691
Other
Used by 98
63Health
Framework npm

Commander.js

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

28,391
MIT
Used by 94
69Health
Library npm

DOM Testing Library

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

3,332
MIT
Used by 87
56Health
Library npm

fs-extra

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

9,589
MIT
Used by 84
95Health
Tool npm

Storybook

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

91,053
MIT
Used by 83
41Health
Library npm

@codemirror/view

The DOM view layer for the CodeMirror 6 code editor, handling rendering, input, and editor chrome.

178
MIT
Used by 81
90Health
Framework PyPI

FastAPI

A modern, high-performance Python web framework for building APIs with automatic validation, serialization, and interactive docs.

102,333
MIT
Used by 76
32Health
Library npm

CodeMirror State

Immutable document, selection, and transaction data structures for the CodeMirror code editor

83
MIT
Used by 73
53Health
Library npm

@monaco-editor/react

Drop the Monaco code editor into any React app without touching webpack, rollup, or bundler config files.

4,741
MIT
Used by 72
90Health
Tool npm

Oxlint

Rust-based JavaScript/TypeScript linter that runs 50-100x faster than ESLint, with zero configuration required.

22,741
MIT
Used by 70

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