Add to ORKGThe main goal of this thesis is to reveal significant imperfections of the popular open-source Content Management Systems (CMS) and to design and implement a core of a custom extensible CMS system. Such a system, based on a modern PHP framework, could be a better choice than open-source CMS systems for webdesigners using it for commercial purposes. There are three open-source CMS systems analyzed from various perspectives in the first chapter: Drupal, CMS Made Simple and TYPOlight. In the second chapter there are introduced benefits from using a modern PHP framework and a custom CMS system is designed. It is completely implemented in the appendix of the thesis. The most important and the most original contribution of this thesis is a design...