In all the new features of Moodle 2.9,the theme designers will really love the support added for implementing renderers as Mustache – logic less templates.
- It is easier to see the final result of the template because the code for a template is very close to what the final HTML will look like
- Because the templating language is intentionally limited, it is hard to introduce complex logic into a template. This make it far easier for a theme designer to override a template, without breaking the logic
For more details, read the Moodle 2.9 release notes here: https://docs.moodle.org/dev/Moodle_2.9_release_notes#For_developers