Contemporary software projects are unique and volatile, leading development teams to modify standard development processes and continue to make adjustments as needed. Adjusting software project development to accommodate the variance and dynamics is called software process tailoring (SPT). Because SPT critically determines how projects are conducted, its performance merits investigation. However, the extant literature lacks empirical evidence of the underlying effects that operate and influence the performance of SPT. Specifically, SPT is a team-based activity that requires the exchange of knowledge and opinions among members to yield an integrative tailoring solution; SPT is also a highly conflicting process involving task and temporal conflicts. Given these characteristics, teams’ operational mechanisms that increase SPT performance remain unknown. To address the aforementioned gaps, this study adopts the transactive memory systems (TMS) theory to develop a research model to explore how a team's TMS affects SPT performance with task conflict and shared temporal cognitions (STC) acting as moderators. By examining 102 software project teams, we found that TMS has a positive impact on SPT performance. Surprisingly, task conflict reduces the effect of TMS on SPT performance, whereas STC amplifies the influence of TMS-SPT performance.