The COVID-19 pandemic is considered as the most crucial global health calamity of the century. It has impacted different business sectors around the world and software development is not an exception. This study investigates the impact of COVID-19 on software projects and software development professionals. We conducted a mining software repository study based on 100 GitHub projects developed in Java using ten different metrics. Next, we surveyed 279 software development professionals for better understanding the impact of COVID-19 on daily activities and wellbeing. We identified 12 observations related to productivity, code quality, and wellbeing. Our findings highlight that the impact of COVID-19 is not binary (reduce productivity versus increase productivity) but rather a spectrum. For many of our observations, substantial proportions of respondents have differing opinions from each other. We believe that more research is needed to uncover specific conditions that cause certain outcomes to be more prevalent.

Open design discussion is a primary mechanism through which open source projects debate, make and document design decisions. However, there are open questions regarding how design discussions are conducted and what effect they have on the design quality of projects. Recent work has begun to investigate design discussions, but has thus far focused on a single communication channel, whereas many projects use multiple channels. In this study, we examine 37 Apache projects and their design discussions, the project’s design quality evolution, and the relationship between design discussion and design quality. A mixed method empirical analysis (data mining and a survey of 130 developers) shows that: I) 89.51% of all design discussions occur in project mailing list, II) both core and non-core developers participate in design discussions, but core developers implement more design related changes (67.06%), and III) the correlation between design discussions and design quality is small. We conclude the paper with several observations that form the foundation for future research and development.

Background: Merge conflicts are a common occurrence in software development. Researchers have shown the negative impact of conflicts on the resulting code quality and the development workflow. Thus far, no one has investigated the effect of bad design (code smells) on merge conflicts. Aims: We posit that entities that exhibit certain types of code smells are more likely to be involved in a merge conflict. We also postulate that code elements that are both "smelly" and involved in a merge conflict are associated with other undesirable effects (more likely to be buggy). Method: We mined 143 repositories from GitHub and recreated 6,979 merge conflicts to obtain metrics about code changes and conflicts. We categorized conflicts into semantic or non-semantic, based on whether changes affected the Abstract Syntax Tree. For each conflicting change, we calculate the number of code smells and the number of future bug-fixes associated with the affected lines of code. Results: We found that entities that are smelly are three times more likely to be involved in merge conflicts. Method-level code smells (Blob Operation and Internal Duplication) are highly correlated with semantic conflicts. We also found that code that is smelly and experiences merge conflicts is more likely to be buggy. Conclusion: Bad code design not only impacts maintainability, it also impacts the day to day operations of a project, such as merging contributions, and negatively impacts the quality of the resulting code. Our findings indicate that research is needed to identify better ways to support merge conflict resolution to minimize its effect on code quality.

Context: Software decay is a key concern for large, long-lived software projects. Systems degrade over time as design and implementation compromises and exceptions pile up. Goal: Quantify design decay and understand how software projects deal with this issue. Method: We conducted an empirical study on the presence and evolution of code smells, used as an indicator of design degradation in 220 open source projects. Results: The best approach to maintain the quality of a project is to spend time reducing both software defects (bugs) and design issues (refactoring). We found that design issues are frequently ignored in favor of fixing defects. We also found that design issues have a higher chance of being fixed in the early stages of a project, and that efforts to correct these stall as projects mature and the code base grows, leading to a build-up of problems. Conclusions: From studying a large set of open source projects, our research suggests that while core contributors tend to fix design issues more often than non-core contributors, there is no difference once the relative quantity of commits is accounted for. We also show that design issues tend to build up over time.

Researchers have investigated the lack of diversity in Free/Open Source Software (FOSS) communities, but there have been few studies on age diversity. We interviewed 11 older FOSS contributors and 6 FOSS community leaders (of any age). This formative study reports on 4 key findings from those interviews: 1) motivations of older contributors, 2) benefits and challenges to contribution, 3) older adults' views on discrimination in FOSS, and 4) ways in which older adults enrich FOSS communities. We found that older adults' contributions are driven by intrinsic motivation, altruism, and community identification. In older adults' most recent contributions, we found that there were more social than technical challenges to participation. Interestingly, the majority of older adults claimed to have witnessed discrimination towards others in FOSS, especially against non-native English speakers and women. This stands in contrast to what the general male FOSS developer population reports. Participants identified 10 ways that older adults add value to FOSS communities. We conclude with guidelines for onboarding older adults.

The global population is aging rapidly, and older adults are becoming increasingly technically savvy. This paper explores ways to engage these individuals to contribute to free/open source software (FOSS) projects. We conducted a pilot diary study to explore motivations, barriers, and the contribution processes of first-time contributors in a real time, qualitative manner. In addition, we measured their self-efficacy before and after their participation. We found that what drove participants were intrinsic motivations, altruism, and internal values, which differed from previous work with older adults and with the general FOSS population. We also found that self-efficacy did not change significantly, even when participants encountered significant barriers or setbacks. The top 3 barriers were lack of communication, installation issues, and documentation issues. We found that asking for and receiving help, and avoiding difficult development environments were more likely to lead to success. To verify these results, we encourage a future large-scale diary study that involves multiple demographics. Given our pilot study, we recommend that future outreach efforts involving older adults focus on how to effectively communicate and build community amongst older contributors.