Participants can indicate their proficiency to other (eg: by wearing a sticker). This can also change in time.
Rock: coders, handy-man, everyone that would like to get their hands dirty and just build, with or without a plan.
Paper: architects, system thinkers, everyone that would like to draw, discuss and iterate on the plan of execution.
Scissor: Decorators, UX designers, graphic designers, crafters, artisans, etc.. the touch that would bring what the rock and paper have created into a beautiful piece of art.
Proficiencies can be used to form balanced and complete teams, or to organize activities / workshops focused on a specific proficiency.