How to Win Friends and Influence People by Carnegie. Old but great for an introvert on the spectrum like me. Human nature doesn't change, but I still don't understand it.

Functional Web Development with Elixir, OTP, and Phoenix: Rethink the Modern Web App by Lance Halvorsen

Elixir and Phoenix have been fantastic for my productivity. I had a fairly short, but steep learning curve in the early days, but LiveView is amazing and replaces quite a bit of client side javascript that previously felt redundant to me. I've been getting a quicker time to completion, and correspondingly being paid faster than when I was working with more traditional stacks like Django or Rails.