I wish I could say it's some lovely architecture, but it's just some glued together python scripts that get the data from the ebay API, categorise the GPUs (I initially tried local LLMs, but hard coded rules work far better), then generate a static site using jinja2 templating. My frontend "framework" is simple vanilla HTML, CSS, and JS.
I suppose I'm living up to the username! I do know how to write decent programs and in other languages, but I'm just so much faster when bodging.
I'm thinking of making similar website for more things, in which case I'd clean up the architecture a bit, but my exams are in a few months and this hasn't been particularly successful so we'll see. I probably shouldn't be spending my weekends programming right now :)