Compass isn't very well maintained and someone I work with even said it may be discontinued. I'd look at a lighter mixin lib like bourbon (http://bourbon.io) and pull other elements from other places (e.g. grid from Susy (http://susy.oddbird.net/), which has now been rewritten to not depend on compass anymore).
Bourbon has Neat (http://neat.bourbon.io/) now, which is a lightweight responsive grid framework. No compass anymore!
Not sure what it's like now, but a fair few of the frontend people I've worked with were complaining about it a few months ago because the mixins it provides were unreliable.