Actually before each template was wrapped in try / catch by modifying a template (see the "generated by hand" code that I've deleted). The essential bit was adding `.end()` to the promise chain, without it `noder.execute` was "swallowing" an exception to reject a promise.

I'm also not sure if we should be using the `notifyScriptError` method to report errors, but since this was existing... In any case any exception should end up written to a console right now.