I added a variety of Volt only cases to the Swig parser. Basically it works and currently it must be installed with npm by referrencing the github commit tarball. I'm sure that it could be improved once its accepted by the maintainers.
So now I'm able to develop with Ninja2 style templates on both the Phalcon and Webpack side. I also created a webpack Nunjucks loader as well.
I'm thinking that once this toolset is better established that it would be good to have the official Phalcon docs link to it. Its all part of the ecosystem and I don't currently see anyone eager to create a PHP only solution. Node seems to be dominating the build environment space now anyways.