I have a helm chart with an optional component. It seems that the preferred way to support optional components is to break them into separate charts and toggle them with tags.

I tried this, but my optional component needs to know a variable from the rest of the chart (the address of a particular service). This causes things to break

Error: render error in "subchart/foo-deployment.yaml": 
template: superchart/templates/_helpers.tpl:14:40: 
executing "superchart.variable <.Values.variable...>: 
can't evaluate field name in type interface {}