In this episode, Jesus Castello, a ruby developer who has been programming since he was 10 years old. He has been a Ruby Developer for 7 years. He teaches Ruby and has a Youtube channel and website. — discusses with the panel his post about Environmental Variables. Jesus teaches what an environmental variable is, and then together Jesus and the panel discuss the uses of environmental variables. One specific topic they go into detail on is credentials and the master key. They also ask him questions about his career teaching Ruby to those on the web.