This paper offers a case study on dialect contact in Máíhiki (Tukanoan, Peru), with the goal of illustrating how documentation of variation can contribute to a general language documentation project. I begin by describing the facts of variation in one dialectally diverse Máíhiki-speaking community. I then argue that the outcomes of dialect mixing in this speech community can be understood only through a fine-grained analysis centering the dialectal composition of the communities of practice to which speakers belonged in early life. The coarse-grained identity categories used in most variationist analyses, such as age and gender, are less informative. After proposing a network theory interpretation of this finding, I discuss its implications for the role of (a) ethnography and (b) the European dialect mixing literature in research on variation in endangered languages. Second, I describe some surprising similarities between this speech community and those described in classic variationist literature. Like urban English speakers, Máíhiki speakers attach less indexical value to morphosyntactic than to phonological variation, and--although their language lacks a standard--engage in indexically motivated style-shifting. I discuss ways to adapt variationist methods to endangered language settings to capture these phenomena, then close with comments on the importance of documenting variation for conservation.