ycssmin is a Node.js library that minifies CSS strings, exposing a simple `cssmin` function that removes whitespace, comments and unnecessary characters (with optional line‑break positioning). It is intended for developers and build‑tool authors who need a lightweight, programmatic way to compress CSS files during web‑asset pipelines. The project is maintained by the YUI team as an up‑to‑date fork of the original node‑cssmin implementation.