A system for testing the effectiveness of webpage configurations is disclosed. Tags indicating dependency between sections of a webpage may be associated with the sections. In response to a version of a first section of a webpage being tested, an associated tag may indicate that the content or behavior of a second section is dependent on the first section. A webpage configuration including content of the first section, and corresponding behavior and content of the second section, may be transmitted to a web client. Data may be collected indicating the effectiveness of the webpage configuration.