Budget of $100. Best system design courses/books in 2023?

Hey everyone, I'm a mid level software engineer doing interview prep. With a budget of $100 or around that, what would be the absolute best system design resource to use? I've checked out https://www.

Hey everyone, I'm a mid level software engineer doing interview prep. With a budget of $100 or around that, what would be the absolute best system design resource to use? I've checked out https://www.designgurus.io and the course on https://bytebytego.com . Both seem to be quite good. I can spend a little more if necessary.