Governance in online communities is an increasingly high-stakes challenge, and yet many basic features of offline governance legacies–juries, political parties, term limits, and formal debates, to name a few–are not in the feature-sets of the software most community platforms use. Drawing on the paradigm of Institutional Analysis and Development, this paper proposes a strategy for addressing this lapse by specifying basic features of a generalizable paradigm for online governance called Modular Politics.