We're going to make it dynamic using the geozones. Besides, class methods can be overwritten using custom models, while constants can't be overwritten without getting a warning [1]. Makes the definition of segments with geozones a little cleaner. I think it’s worth it, compared to the slight memory gain of using a constant [2]. [1] warning: already initialized constant UserSegments::SEGMENTS [2] https://stackoverflow.com/questions/15903835/class-method-vs-constant-in-ruby-rails#answer-15903970