Stuck following the Friss analytics build js widget tutorial

I was following this tutorial.

https://shiny.rstudio.com/articles/js-build-widget.html
I'm able to get the example working in my viewer. When I try creating the gauge in a Shiny context I get this error:
Error in C3GaugeOutput() : could not find function "C3GaugeOutput"

Does anyone know the reason for this? Thanks!

I accidently removed some autogenerated script. My fault!