I'm sorry. In the first three parts I have a bad copy-paste-error in the title. 'Build' was missing an 'u'. Thanks to @marczobec for pointing it out.
And over the weekend I made a decision. I will drop the TDD part of this series. I realized that I wanted to much. TDD would just distract from the main topic: Building an app without Interface Builder. Maybe I will show TDD in a later series.