Probably not appropriate for a large poly-glot organization, but I really like creating shared JS libraries that can be used in the browser and also in Node.js

Probably not appropriate for a large poly-glot organization, but I really like creating shared JS libraries that can be used in the browser and also in Node.js apps. For game development, having the game logic in a shared library makes server-side validation and client-side prediction really easy and prevents code duplication. I'm sure there is some reason it's all a horrible idea but almost all my projects these days use React front-ends and Node.js back-ends and a shared library used by both, ideally containing most of the complex logic. This seems like a neat version of that that might be useful in an organization which uses many different languages.