This might be of interest to the Pike and/or Roxen community:
https://www.npmjs.com/package/remixml
I just launched it. Using it in a Single-Page-Application website. Any critical feedback is welcome (I'm currently the only user, so changes in the API are easy and still allowed).
From the description:
Remixml is an XML/HTML macro language/template engine.
The language and primitives used blend in completely with standard XML/HTML syntax and therefore integrate smoothly with existing XML/HTML syntax colouring editors.
Requirements It runs inside any webbrowser environment (starting at IE11 and up).
For historical reference: Remixml was originally inspired by RXML, the Roxen webserver macro language.