The Humanities Cluster invests a lot of effort in developing infrastructure and tools for digital research. As scholars we want those tools to be easy to use and don't want to bother with many of the technical details. But their ease of use often makes it hard to check if there is a devil in those details who we should want to meet. Digital tools can do a lot of work for us, but only because they are based on a lot of assumptions. Which of these assumptions are important to consider in research? And how can we develop infrastructure and tools that wear their assumptions on their sleeves and that invite us to reflect on their impact? In this talk I will present our research in attempting to address these questions. We have developed conceptual frameworks and techniques for digital tool criticism and evaluation and for thinking and communicating about digital data processes in research. I will discuss the lessons we have learned from bringing these frameworks and techniques into practice and how we can incorporate these lessons in digital humanities research methodology and in developing digital infrastructure.