Thoughts on SSR: Do It
Cloud compute is cheap and efficient now. Certainly better than doing it on your customer’s devices. For a very brief time in web dev history it made sense to offload the work to the user. Probably the biggest motivator for SPAs. But we should go back. Less browser JS pixel pushing and more hard work on the server. The only thing I’d change is long running server processes.
I appreciate the idea of starting from
<div id=app /> and building the app from there. Holding, changing, relaying state while updating the UI with interactions.
Take that clean-slate mental model up a level to the HTTP request. You've got the essentials: a path, a body/params, and a cookie.
Handle it in a cloud function: get the session, build/mutate state, and respond with semantic HTML (or JSON).
Make some HTML with
<form>s, go to town with some CSS, and enhance with JS.
Wait for another request.