The only part of JavaScript that's tied to working with web UI is the DOM API, which isn't even a part of the ECMAScript standard but rather set by the W3C and meant to be language-independent. I think Python could have worked out on the client-side but there were other options and none of them lasted. Give JS a more serious look. You might be surprised to discover that it has some unique features that make it attractive as a general-use language. I think JS has a lot to do with why people suddenly wanted closures in Java or that they implemented proper first class funcs in C#. It's exceptionally good at event-driven paradigms, normalization and reducing complexity, which is exactly what was needed on the client-side but also serves as a powerful feature-set in general use IMO. It's good at letting you set your own paradigm. If you don't love callback-passing-intensive code, that's something you can bury under an interface that appeals to you more.