Mastering programming in Joomla! is not really easy. Joomla! is an extensive framework and there are many conventions and defaults that make life easier. The downside is that as a novice in Joomla! programming, it is sometimes difficult to understand the execution flow. This book does a good job explaining the structure of Joomla! for programmers. It is far better than all other books that I've found so far. It explains all major building blocks and uses the code of core components to explain the underlying mechanisms. That's all great.
As reference material it often tough to find the adequate location with info. Also, I would have prefered when portions of some chapters would have moved to appendices. This allows to concentrate on the explanetory text while reading and efficient searching while looking for precise descriptions.
I hope that someday, there will be a ref 2 of this book, in which the structure has matured.
I am new to joomla so thought it would be good to see how everything works behind the scenes. I am a competent PHP programmer but reading this book has been a real struggle. It does not explain the concepts well enough in my opinion and after reading 80% of this book i still wouldnt feel at all comfortable if i had to write my own extension in joomla. Personally if i had my time over i wouldnt buy this book again.