There are a number of integrations that are out there (HTMLBars, Ember Handlebars, etc) or desired (i18n preprocessor, html-aware minimizer, html-aware linter).

We should strongly consider formalizing the parser/compiler APIs into a system that would be consumable and pluggable at the various levels.

This may take the form of AST/Opcode API formalization or similar. The SpiderMonkey AST model comes to mind.