It’s possible to build a gem that wraps the Dart Sass native version. There’s been a small team working on the Embedded Sass engine and also the Embedded Host Node.js wrapper.
At the moment, the team is only focused on bringing this to work and be compatible with node-sass (the libsass version for node and by far our most popular version). Specifically what makes it complicated and the need for that whole project is that there are many JS-extensions for Sass, because for node-sass we made an API where you can define custom functions in JS and then call them from your Sass code.
Then again, I’m not really sure how you all are using Sass. I see that sass-rails uses sassc, and I don’t think that does anything more than a straightforward compilation phase.
You could do a very, very, very simple wrapper around the Dart Sass and use dart2native to have static builds. It wouldn’t be extensible, but it would be do similar to what a command line compile could do.
-hampton.