Anyone created their own “pre-workout” mix?

It’s so dang expensive to buy, but I find I get some benefits from it.

I use Optimum Nutrition. I guess some people have an itching reaction to Beta Alanine. I don’t have any issues.

But I’m curious about what you would put into a pre-workout (or even a post workout for the sake of discussion) and why?

Also, it is possible to source all of these ingredients separately in a high quality form?

An alternative would be to model an ideal mixture and ask a compounding pharmacy to mix for you. Maybe a years supply at a time. Might be reasonable price? The optimum nutrition can be $40 or more for a one month supply. But it’s fairly basic ingredients.

Am I reinventing the wheel? Is this already out there somewhere?

Thanks everyone.