NippleJS is a vanilla virtual joystick library for touch and mouse interfaces, designed for mobile games, remote controls, and interactive web applications. The core library in `packages/nipplejs/` provides a lightweight, dependency-free joystick with three modes (dynamic, semi, static), multitouch support, and extensive event-driven APIs. The architecture is built around a Factory singleton managing Collections, each of which manages multiple Joystick instances. The library is written in TypeScript, with thorough unit tests and Playwright end-to-end tests covering event accuracy, mode behavior, cleanup, and edge cases. The repository also includes a documentation site built with Astro, featuring five interactive game demos that showcase library features, along with a monorepo structure for tools and tests. While the core library is modern and well-tested, some tooling (ESLint 8, Husky v4) and the workspace Yarn version mismatch indicate minor technical drift.