Relatively short read that covers a number of widely accepted SDLC best practices like CI/CD, TDD, code linting, etc. and shows examples of metrics that can be used to track them.
I recommend it for new college/bootcamp grads that haven't worked in industry yet and are perhaps familiar with technology/theory but not full SDLCs. I don't think it's useful for any professional that's been practicing a few years in a workplace that has embraced or discussed best practices or agile development; it will lack insight and depth for them. The example metrics may be useful for managers looking for inspiration, but most are difficult to instrument existing processes with, and the book will offer little help on that front.