Got it back up now, but via Cloudflare I'm still seeing millions of POST requests per hour. Thankfully they aren't hitting the backend anymore.
One point I had made was that for 13 years I've served the site from a VPS without having to use Cloudflare. Now, apparently a few people (or one person) decided to point some sort of little botnet at it, and I have to use Cloudflare.
Gone are the days when I could smugly remark my website was still up when Cloudflare was down :(
