“Just JavaScript?”: It's More Complicated Than You Think

In the programming world, "Just JavaScript" is a phrase often misused. This article explores the complexities of JavaScript, pointing out that many seemingly simple .js files actually rely on browser APIs, Node.js environment variables, JSX compilation, preprocessors, TypeScript type annotations, and more. The choice of runtime environment and toolchain greatly affects the executability of the code. The author uses a series of examples to illustrate that only "vanilla" JavaScript code, detached from specific runtime environments and toolchains, can truly be called "Just JavaScript."