More info on the visitor pattern, which was originally published by the Gang of Four:

https://en.wikipedia.org/wiki/Visitor_pattern

Rarely seen in its pure form in the wild, but it's vastly useful, and surprisingly versatile, when you need it.

FYI, the layout is unreadable on mobile Firefox (on Android fwiw; looks fine in Chrome).

Author here! I worked on our babel plugin for React Native autocapture from day one. It's been a pretty interesting project. Would be happy to answer any questions you have!