Stability in the production and transmission of texts has been a taken-for-granted feature of communicative acts for much of history. In the past, this fixity (i.e., the reliability of texts not to change over space and time) has arisen from the interaction between immutable technologies (used to produce text) and social rigidity (in the structure and practices of discourse communities where texts are produced and consumed). These interactions provided stable settings fostering the gradual development of rich communicative genres which, in turn, further contributed to fixity in communicative acts. In the current era of virtual communities and digital documents, this relationship between technology, social context, and fixity has been loosened. We claim the new burden for providing fixity in communications is being met by increased reliance on genre. To support this claim, we examine the four-way relationship between technologies, social contexts, social practices and genre by considering example digital documents produced by two different discourse communities.