DevOps Handbook is a fantastic guide for IT organizations, that describes the ways of improving the technology value stream - the process required to convert a business hypothesis into a technology-enabled service that delivers value to the customer.

Clean Architecture is the "Art of War" of the software industry. It was written by a professional who has been through many tough battles, both wins, and losses. Uncle Bob talks about timeless topics of software development that are just as applicable today as they were fifty years ago.

Doing things right doesn't matter unless you do the right thing. "Specification by Example" by Gojko Adzic is about delivering the right software. Adzic has interviewed many successful teams and discovered that their ways of software development are quite similar. These ways or processes are based on a close collaboration between all the parties, including business representatives. It begins by understanding the business goals. It continues with creating a specification and utilizing it for software development and verification. It is finalized by providing living documentation which reflects the current software state and behaviour.

"Specification by Example" helped me to understand how to do behaviour-driven development (BDD). It is an excellent reading for a software craftsman.

Refactoring is a book by Martin Fowler about what a fellow developer might describe as "a process of improving the code quality."

I highly recommend this book to software professionals who want to improve and formalise their refactoring skills.