Are you familiar with the concept of a Markov Chain? (If not, it's a simple tool that technically works better than randomly guessing for predicting stock movement.) I designed a very intense neural network meta-architecture, applied it, and the results were the same as if I'd used a basic Bayes model or Markov Chain. Which is a little humorous; I very much used a bulldozer to sweep the garage.

I used close minus open to determine up vs. down movment. Can't remember the lookback, but was predicting the immediate next day. Over the entire US market, a basic Markov-based model can predict the next day 52.5% of the time or something like that. (Given 1000+ stocks, you guess which direction all will go, 52.5% will be correct guesses.)

For what it's worth, I don't really know the details of the statistical tools. I do have a good grasp of train/test/validate sets, so I know what my results meant.

I have to advocate for the vibe-coded mess-colony.

There are applications where it either works or it doesn't, and it's simultaneously obvious whether it does. Think stock price prediction software. I've killed time in the evenings verbally chatting with agents about that specifically, and what emerged worked! It didn't work well, but it clearly outperformed randomness, and I was able to verify that myself easily.

I didn't look at a line of code, but I had an absolute blast.