Onboarding in software engineering

Many software developers struggle to understand code written by others, leading to increased maintenance costs. Research on program comprehension to date has primarily focused on individual developers attempting to understand code. However, software developers also work together to transfer understanding of their codebases. This activity is common during the onboarding process, when a new developer has joined a project. This study uses a Grounded Theory approach to explore the information passed from expert to newcomer, the techniques used during onboarding sessions and the value of this information to the newcomer. The theory is grounded in recordings of twelve onboarding sessions, supplemented with interviews and questionnaires, and answers questions about the representation of code, the support o ered to newcomers and the problems encountered during the onboarding process. In addition to providing a focused study of the content of onboarding sessions, this study reveals some novel aspects of software comprehension (in particular the need for the Temporal and Rationale views of the code in addition to Structural and Algorithmic) and provides a set of recommendations to increase the e ectiveness of onboarding sessions. The theory is evaluated for both t and generalisability, demonstrating its applicability to industry, and linked to previous work on software comprehension, concept and feature location, information seeking, information push and pull, and onboarding.