Looking for good books on Immutable Infrastructure I am looking for the best books on Immutable Infrastructure. I am interested in books on theory and application. Thank you.
Although I am willing to bet that this answer may not age well, I would suggest 

"Infrastructure as Code" by Kief Morris for the "theory" part.

For the "application" part, I would suggest "Terraform up and Running" by By Yevgeniy Brikman.