@jsenv/assert is a lightweight, modern JavaScript assertion library for Node.js and browsers. It provides a clean and intuitive API to verify code correctness and simplify testing. Featuring clear messaging upon failure, it supports strict equality, deep equality, type checking, regexp matching, and more. Designed for ease of use and integration with various testing frameworks, @jsenv/assert ensures reliable and readable assertions within your JavaScript projects. Its focus on simplicity makes it accessible for both beginners and experienced developers.