The SOLID Principles are Universal

I've spent a significant portion of my career thinking about the SOLID principles. I wrote about them in the context of JavaScript and TypeScript, I built InversifyJS largely because of them, and I've had countless conversations with other developers about whether they belong in the JavaScript world at all. Over the years, many people have pushed back, arguing that SOLID is an object-oriented thing, that it only matters if you're writing Java or C#, and that it doesn't apply to their world. I respectfully disagree. In fact, the more I look around, the more I'm convinced that the SOLID principles are not about object-oriented programming at all. They are universal design principles that manifest everywhere, whether you realise it or not. You'll find them in CSS utility frameworks, in functional programming, and even in the way we're building AI agents today. Let me show you what I mean. 1. Tailwind CSS When Tailwind CSS first gained popularity, I remember many developers (including myse