Dmitry Eliseev has been a web developer since 2008 and specializes in server-side programming on the PHP and PHP frameworks. Since 2012 he has authored his personal blog, https://elisdn.ru, about web development in general and about the Yii Framework in particular. His blog has become a well-known resource in the Russian Yii community. He is an active member of a Russian-language forum: https://yiiframework.ru. Dmitry is interested in developmental best practices, software architectures, object-oriented programming, and other approaches. He is an author and a presenter of practical courses about the principles and best practices of object-oriented programming and the use of version control systems. And also he is an author of webinars, the Yii2 Framework, and common developmental subjects. He practices teaching and counseling by development on frameworks and using the principles of software design and improvements in common code quality. This is his first book.