What is the best technical book you've read in 2021?

I'm not finished with it yet, but currently reading designing data-intensive applications and it's probably the most technical I've read. I also have to start digging into an algo book as I move into my final year of college.

Designing Electronics that Work, but Hunter Scott: http://designingelectronics.com/

Outstanding book, and attached resource list for designing and building electronics projects. Great for startups etc.

Web Scalability for Startup Engineers was a very good high level one I read as a pre-read to DDEA