> I vibe coded...

Well, there ya go.

To be fair, it says the attention was unexpected, and this was just a coding exercise... And the port-mortem shows what I'd hope to see: digging in and figuring out root causes. So I'm not judging OP poorly over this.

But still. Launching a vibe-coded app that accepts input from anonymous users is just asking for trouble. I'm frankly surprised it ran as long as it did without such problems. (Although I did see a few weenies swimming around even before the problem hours.)

The lesson I'd pull from this is that if you are not the type of dev who could put together a post-mortem along these lines... don't launch a vibe-coded app.