I am experimenting with using Twig template engine within Silverstripe by getting a version of the Simple theme to work with Twig https://github.com/chris-hall-hu/simple-silverstripe-twig.
I am using a fork of https://github.com/camspiers/silverstripe-twig to make twig available so that I can add extensions, functions etc.
Probably going to be a bit of slow-burner have little free time at the moment, and have only just started learning Silverstripe, really I am looking for options next year probably after SS version 4 is released, doing this is helping me learn Silverstripe, plus I want to get a better knowledge of Twig under the hood.
It may well be better to just use different approaches with Twig, however there is probably a benefit to making options to work with require, $layout etc. etc. so far just got require working.
I am not proposing replacing SS templating with Twig wholesale the native templating looks pretty good already ;), personally though I may have need to work with multiple frameworks and people who already know Twig, possibly with some custom Twig extensions also.
Any comments or heads-up re. things I may have problems with gratefully received.