Developer Marketing Does Not Exist: The Authentic Guide to Reach a Technical Audience | 
pickI know this is different than the genres I usually read. I read it for work, however, I found it quite relatable. Traditional marketing doesn‘t work with developers. You want to work with them - educate them, train/teach them, give them support for free to gain their trust & hope they use your products. Really helpful, tangible advice in this book.