Ivoire is a small JavaScript library that provides a deterministic pseudo‑random number generator built on the Mersenne Twister. It offers simple methods such as `random()`, `integer()`, `natural()`, `pick()`, `pick_some()` and `shuffle()` for generating numbers and sampling arrays, and is designed to be extensible via plugins. The package is aimed at Node.js developers who need reproducible random sequences for testing, simulations, or games.