Follow that Sketch: Lifecycles of Diagrams and Sketches in Software Development Jagoda Walny, Jonathan Haber, Marian D¨ ork, Jonathan Sillito and Sheelagh Carpendale Department of Computer Science University of Calgary Calgary, Alberta Email: {jkwalny, jmhaber, mdoerk, sillito, sheelagh}@ucalgary.ca Abstract—Informal visualization in the form of sketching and diagramming has long been an established practise of professionals working in the fields of design, architecture, and engineering. Less is known, however, about the sketching and diagramming practices of computer scientists and software de- velopers. Through a series of interviews with computer science re- searchers who develop software, we probed the purpose, contexts, and media in which they created and re-created sketches and diagrams, and the ways in which these informal visualizations evolved over time. Through our analysis we created visualizations of the observed sketching and diagramming lifecycles, which can contribute to a better understanding of the roles of sketching and diagramming in software development. I. I NTRODUCTION Visualization through sketching and diagramming plays an important role in the design process in various domains, including architecture, design, and engineering [6], [9], [19]. Such visualizations range from informal sketches to more for- mal diagrams following a standard visual language. They are used for everything from exploring, formation, and recording of ideas, to increasing one’s understanding of concepts and communicating ideas to others. They also have considerable value within organizations–some engineers and architects save all sketches made during the course of a project as a record of all ideas and decisions made [6]. Although there has been much work in understanding the visualization practises of those designing physical objects (the aforementioned architects, designers, and engineers), it is unclear how much of this knowledge is transferable to software developers, who design digital objects. Software development differs from these domains in that it involves a combination of concrete visual elements such as user interfaces and more abstract elements like the structure of the source code. In our experience, software developers create and work with a range of paper-based as well as digital visualizations of software concepts in their development work. These visualiza- tions go beyond established visual formalisms such as UML, wireframes, or storyboards, and do not always use the available computer-supported tools, such as diagramming software or auto-generated UML diagrams. We have seen that software developers also draw their own informal visualizations, on various analog and digital media, that do not adhere strictly to these established formalisms. To better understand how to provide tool support for in- tegrating these visuals into developers’ workflows we have conducted a qualitative study about the creation, use and transformation of diagrams, including transformations between paper and digital media. Rather than studying specific diagram types, we sought to gain an understanding of the various ways in which software developers currently use diagrams to develop ideas and solve problems. Based on qualitative inter- views, we followed various sketches through their lifecycles involving a range of transitions and media types. For this study, we recruited individuals who use sketches or diagrams for software design and development. These participants were not part of teams with formal practices in place that would influence how diagrams were to be used. Selecting these participants allowed us to study what types of sketching workflows software developers and researchers may tend towards naturally. By following individual sketches and diagrams through their lifecycles, we contribute a number of ways in which informal visualizations can have value beyond their initial creation (including as memory aids and for sharing with colleagues), and we characterize a range of actual sketch lifecycles that occurred in software development settings. II. DIAGRAMS AND SKETCHES:SCOPE AND DEFINITIONS We found that the visuals used by our study participants varied on a continuum from very sketchy to more refined (see Figure 1). One end of this continuum is similar in spirit to Buxton’s [3] characterization of sketches as: appearing to be made quickly; disposable; plentiful; following conventions that distinguish them as sketches; having a fluidity evoking “a sense of openness and freedom”; containing minimal detail; being no more refined than the certainty in the creator’s mind; “suggesting” rather than “telling”; and being intentionally ambiguous. The other end is characterized by formal draw- ings with crisp lines, often following some predefined visual language or conventions. Informal Formal sketchy quality rigid quality Diagrams Sketches Fig. 1. Sketches and diagrams can be situated along a formality spectrum according to their sketchy vs rigid nature.