Open Source Packages
Libraries, frameworks, tools, and SDKs used by the apps in this directory — scored the same way as the apps themselves.
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prettier
An opinionated code formatter that enforces consistent style across every language your project speaks.
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.
typescript-eslint
The official meta-package bundling the TypeScript ESLint parser, plugin, and rule presets behind a single typed config() helper.
Playwright
Cross-browser end-to-end web testing and browser automation with a single API for Chromium, Firefox, and WebKit.
React Testing Library
Simple and complete React DOM testing utilities that encourage good testing practices.
jest-dom
Custom Jest matchers for asserting on the state of the DOM in your tests.
jest
Delightful JavaScript testing with zero-config setup, snapshots, mocking, and coverage
user-event
Simulates the full sequence of real browser events so Testing Library tests behave the way an actual user does.
Marked
A fast, low-level Markdown compiler that parses CommonMark and GFM into HTML in Node.js, browsers, or the CLI.
serde_json
The de facto standard JSON library for Rust, built on the Serde serialization framework
testify
The essential Go toolkit for assertions, mocks, and structured test suites.
js-yaml
A fast, complete YAML 1.2 and 1.1 parser and serializer for JavaScript.
pytest
The Python testing framework that makes writing small tests easy and scales to complex functional test suites.
yaml
A definitive TypeScript parser and stringifier for YAML, supporting 1.1 and 1.2 with comment and CST access.
Commander.js
The complete, battle-tested framework for building Node.js command-line interfaces.
DOM Testing Library
Simple, framework-agnostic DOM query utilities that test your UI the way real users interact with it.
fs-extra
Drop-in replacement for Node's fs module adding copy, remove, mkdirs, and JSON helpers with native promise support.
Storybook
The industry-standard workshop for building, documenting, and testing UI components in isolation, across every major frontend framework.
FastAPI
A modern, high-performance Python web framework for building APIs with automatic validation, serialization, and interactive docs.
Oxlint
Rust-based JavaScript/TypeScript linter that runs 50-100x faster than ESLint, with zero configuration required.
diff
A battle-tested JavaScript library for computing and applying text diffs at the character, word, line, sentence, CSS, or JSON level.
undici
A fast, spec-compliant HTTP/1.1 client for Node.js, built from scratch with zero runtime dependencies
tempfile
A secure, cross-platform Rust library for temporary files and directories that clean up automatically on drop.
Pino
A super fast, low-overhead JSON logger for Node.js applications.