Thanks for looking at the lib!
Polling is typically the kind of thing I usually prefer to handle fully manually in JS. That's what I do for my own web apps.
Even if I added a specific HTML tag attribute for polling, at the end, there will always be a missing something, and I'll end up writing JS anyway. So for this kind of thing, I don't think a lib is necessary: you just setTimeout / setInterval in the script that runs when the view is loaded:
Swap.loaders[".my_view_with_polling"] = () => {
update_task = setTimeout(do_polling, 1000);
...
return () => {
// unloader function when we quit this view
clearTimeout(update_task);
};
};