Web tech never ceases to amaze me in how they keep over-engineering simple things. You have a backend service, you implement it in whatever language you want,

Web tech never ceases to amaze me in how they keep over-engineering simple things. You have a backend service, you implement it in whatever language you want, presumably C++ if you care about performance or are doing something non-trivial. It provides REST and WebSocket endpoints to input and receive data. You have your GUI to visualize the thing. Common sense is to have the overall structure in HTML and fill it in with JavaScript that queries the backend. The advantage is that you have a rapid and interactive development environment in the browser and can quickly iterate on a useful GUI without touching the backend. Then, moving the GUI to be part rendered on a server, that sounds like a terrible idea, a good way to increase latency and to add load onto your servers. If you need to do that to get decent performance then probably your backend API is inadequate. Compiling the code also breaks the whole point as it makes the development non-interactive.