Two good reasons to not use YAML for this interactive example: 1. intermediate steps in YAML are often invalid documents (breaks the update on every key press)

Two good reasons to not use YAML for this interactive example: 1. intermediate steps in YAML are often invalid documents (breaks the update on every key press) 2. you have to be trained to write YAML. It is quite easy to make a syntax mistake with YAML if you aren’t used to writing it. Not good for an interactive experience