(edited) and the `to_ruby` part:

https://www.dropbox.com/s/848ici6sru7cvny/Screenshot%202019-04-18%2015.08.37.png?dl=0 => @FlorianDoublet's work:

https://www.dropbox.com/s/2p65r80wwtbrspv/Screenshot%202019-04-18%2015.12.23.png?dl=0

🙂