Ha, I know. It's a single VM instance right now. I have been thinking of migrating to Gatsby for quite some time now. This unexpected traffic and the server limitations give me a reason to get working on it!
You can write much of your site in raw HTML. For example, your right panel– you can write it in raw HTML, annotate it with some tags. Make it an iframe, just use CSS to get rid of the borders, or an XMLHTTPRequest. As long as you make good use of CSS, you can have a few tags and it'll work.