Comment by c-smile

To make it even closer to Svelte, Sciter has native signal() implementation, so

   let bottles = signal(0);

   function Beers() {
       return <span .bottles multiple={bottles.value > 1}>{bottles.value} bottles of beer</span>
   }

   document.body.append(<Beers/>);

That can be updated by simply changing signal:

   bottles.value = 42; // Party time!

Note: this does not require any preprocessors or precompilations.