Ricardo Colomo-Palacios

Steffen Herbold, Alexander Trautsch, Benjamin Ledel et al.

Context: Tangled commits are changes to software that address multiple concerns at once. For researchers interested in bugs, tangled commits mean that they actually study not only bugs, but also other concerns irrelevant for the study of bugs. Objective: We want to improve our understanding of the prevalence of tangling and the types of changes that are tangled within bug fixing commits. Methods: We use a crowd sourcing approach for manual labeling to validate which changes contribute to bug fixes for each line in bug fixing commits. Each line is labeled by four participants. If at least three participants agree on the same label, we have consensus. Results: We estimate that between 17% and 32% of all changes in bug fixing commits modify the source code to fix the underlying problem. However, when we only consider changes to the production code files this ratio increases to 66% to 87%. We find that about 11% of lines are hard to label leading to active disagreements between participants. Due to confirmed tangling and the uncertainty in our data, we estimate that 3% to 47% of data is noisy without manual untangling, depending on the use case. Conclusion: Tangled commits have a high prevalence in bug fixes and can lead to a large amount of noise in the data. Prior research indicates that this noise may alter results. As researchers, we should be skeptics and assume that unvalidated data is likely very noisy, until proven otherwise.

Martin Forsberg Lie, Mary Sánchez-Gordón, Ricardo Colomo-Palacios

Background: Medical device development projects must follow proper directives and regulations to be able to market and sell the end-product in their respective territories. The regulations describe requirements that seem to be opposite to efficient software development and short time-to-market. As agile approaches, like DevOps, are becoming more and more popular in software industry, a discrepancy between these modern methods and traditional regulated development has been reported. Although examples of successful adoption in this context exist, the research is sparse. Aims: The objective of this study is twofold: to review the current state of DevOps adoption in regulated medical device environment; and to propose a checklist based on that review for introducing DevOps in that context. Method: A multivocal literature review is performed and evidence is synthesized from sources published between 2015 to March of 2020 to capture the opinions of experts and community in this field. Results: Our findings reveal that adoption of DevOps in a regulated medical device environment such as ISO 13485 has its challenges, but potential benefits may outweigh those in areas such as regulatory, compliance, security, organizational and technical. Conclusion: DevOps for regulated medical device environments is a highly appealing approach as compared to traditional methods and could be particularly suited for regulated medical development. However, an organization must properly anchor a transition to DevOps in top-level management and be supportive in the initial phase utilizing professional coaching and space for iterative learning; as such an initiative is a complex organizational and technical task.