To manage work interdependencies, online communities draw on a variety of arm's length coordination mechanisms offered by information technology platforms and associated practices. However, Òunresolved interdependenciesÓ remain that cannot be addressed by such arm's length mechanisms. These interdependencies reflect, for example, unidentified or emerging knowledge-based dependencies between the community members or unaccounted relationships between ongoing community tasks. At the same time, online communities cannot resort to hierarchical coordination mechanisms such as incentives or command structures to address such interdependencies. So, how do they manage such interdependencies? To address this question, we conduct an exploratory, theory-generating case study involving qualitative and computational analyses of development activities within an open source software community: Rubinius. We analyze the ongoing management of interdependencies within the community and find that unresolved interdependencies are associated with alternatively structured sequences of activities, which we define as routines. In particular, we observe that two distinct classes of interdependenciesÑdevelopment and developer interdependenciesÑare associated with alternative forms of routine variation. We identify two generalized routine componentsÑdirect implementation and knowledge integration, which address these two distinct classes of unresolved interdependencies. In particular, direct implementation deals with development interdependencies within the code that are not already coordinated through modular interfaces, while knowledge integration resolves unaccounted interdependencies between developers. We conclude with implications for research into organizing principles for online communities and note the significance of our findings for the study of coordination in organization studies in general.