Klaas-Jan Stol

Scaling agile methods to regulated environments: an industry case study

Agile development methods are growing in popularity with a recent survey reporting that more than 80% of organizations now following an agile approach. Agile methods were seen initially as best suited to small, co-located teams developing non-critical systems. The first two constraining characteristics (small and co-located teams) have been addressed as research has emerged describing successful agile adoption involving large teams and distributed contexts. However, the applicability of agile methods for developing safety-critical systems in regulated environments has not yet been demonstrated unequivocally, and very little rigorous research exists in this area. Some of the essential characteristics of agile approaches appear to be incompatible with the constraints imposed by regulated environments. In this study we identify these tension points and illustrate through a detailed case study how an agile approach was implemented successfully in a regulated environment. Among the interesting concepts to emerge from the research are the notions of continuous compliance and living traceability.

Two's company, three's a crowd: a case study of crowdsourcing software development

Crowdsourcing is an emerging and promising approach which involves delegating a variety of tasks to an unknown workforce - the crowd. Crowdsourcing has been applied quite successfully in various contexts from basic tasks on Amazon Mechanical Turk to solving complex industry problems, e.g. InnoCentive. Companies are increasingly using crowdsourcing to accomplish specific software development tasks. However, very little research exists on this specific topic. This paper presents an in-depth industry case study of crowdsourcing software development at a multinational corporation. Our case study highlights a number of challenges that arise when crowdsourcing software development. For example, the crowdsourcing development process is essentially a waterfall model and this must eventually be integrated with the agile approach used by the company. Crowdsourcing works better for specific software development tasks that are less complex and stand-alone without interdependencies. The development cost was much greater than originally expected, overhead in terms of company effort to prepare specifications and answer crowdsourcing community queries was much greater, and the time-scale to complete contests, review submissions and resolve quality issues was significant. Finally, quality issues were pushed later in the lifecycle given the lengthy process necessary to identify and resolve quality issues. Given the emphasis in software engineering on identifying bugs as early as possible, this is quite problematic.

A systematic review of comparative evidence of aspect-oriented programming

Context: Aspect-oriented programming (AOP) promises to improve many facets of software quality by providing better modularization and separation of concerns, which may have system wide affect. There have been numerous claims in favor and against AOP compared with traditional programming languages such as Objective Oriented and Structured Programming Languages. However, there has been no attempt to systematically review and report the available evidence in the literature to support the claims made in favor or against AOP compared with non-AOP approaches. Objective: This research aimed to systematically identify, analyze, and report the evidence published in the literature to support the claims made in favor or against AOP compared with non-AOP approaches. Method: We performed a systematic literature review of empirical studies of AOP based development, published in major software engineering journals and conference proceedings. Results: Our search strategy identified 3307 papers, of which 22 were identified as reporting empirical studies comparing AOP with non-AOP approaches. Based on the analysis of the data extracted from those 22 papers, our findings show that for performance, code size, modularity, and evolution related characteristics, a majority of the studies reported positive effects, a few studies reported insignificant effects, and no study reported negative effects; however, for cognition and language mechanism, negative effects were reported. Conclusion: AOP is likely to have positive effect on performance, code size, modularity, and evolution. However its effect on cognition and language mechanism is less likely to be positive. Care should be taken using AOP outside the context in which it has been validated.

Grounded theory in software engineering research: a critical review and guidelines

Grounded Theory (GT) has proved an extremely useful research approach in several fields including medical sociology, nursing, education and management theory. However, GT is a complex method based on an inductive paradigm that is fundamentally different from the traditional hypothetico-deductive research model. As there are at least three variants of GT, some ostensibly GT research suffers from method slurring, where researchers adopt an arbitrary subset of GT practices that are not recognizable as GT. In this paper, we describe the variants of GT and identify the core set of GT practices. We then analyze the use of grounded theory in software engineering. We carefully and systematically selected 98 articles that mention GT, of which 52 explicitly claim to use GT, with the other 46 using GT techniques only. Only 16 articles provide detailed accounts of their research procedures. We offer guidelines to improve the quality of both conducting and reporting GT studies. The latter is an important extension since current GT guidelines in software engineering do not cover the reporting process, despite good reporting being necessary for evaluating a study and informing subsequent research.

Report on the Second SEMAT Workshop on General Theory of Software Engineering (GTSE 2013)

Many academic disciplines have general theories, which apply across the discipline and underlie much of its research. Examples include the Big Bang theory (cosmology), Maxwells equations (electrodynamics), the theories of the cell and evolution (biology), the theory of supply and demand (economics), and the general theory of crime (criminology). Software engineering, in contrast, has no widely-accepted general theory. Consequently, the SEMAT Initiative organized a workshop to encourage development of general theory in software engineering. Workshop participants reached broad consensus that software engineering would benefit from better theoretical foundations, which require diverse theoretical approaches, consensus on a primary dependent variable and better instrumentation and descriptive research.

Reporting Empirical Research in Open Source Software: The State of Practice

Background: The number of reported empirical studies of Open Source Software (OSS) has continuously been increasing. However, there has been no effort to systematically review the state of the practice of reporting empirical studies of OSS with respect to the recommended standards of performing and reporting empirical studies in software engineering. It is important to understand, how to report empirical studies of OSS in order to make them useful for practitioners and researchers.

Key factors for adopting inner source

A number of organizations have adopted Open Source Software (OSS) development practices to support or augment their software development processes, a phenomenon frequently referred to as Inner Source. However the adoption of Inner Source is not a straightforward issue. Many organizations are struggling with the question of whether Inner Source is an appropriate approach to software development for them in the first place. This article presents a framework derived from the literature on Inner Source, which identifies nine important factors that need to be considered when implementing Inner Source. The framework can be used as a probing instrument to assess an organization on these nine factors so as to gain an understanding of whether or not Inner Source is suitable. We applied the framework in three case studies at Philips Healthcare, Neopost Technologies, and Rolls-Royce, which are all large organizations that have either adopted Inner Source or were planning to do so. Based on the results presented in this article, we outline directions for future research.

Challenges in using open source software in product development: a review of the literature

Component-Based Software Development has become a popular approach to building software intensive systems. Besides using Commercial Off-The-Shelf components, an organization may choose to use Open Source Software components. Using OSS has been reported to have many benefits, but there are also challenges involved. Understanding the potential challenges of using OSS in developing products is important for practitioners, so they become aware of them and can anticipate them and take appropriate measures to address these challenges. We have performed a thorough review of the literature to identify challenges that may arise, as reported in the literature. This paper presents and discusses these findings. Researchers can discuss potential causes and solutions of our synthesized findings as well as benefit from provided references to literature on OSS challenges as input for future research.

The use of empirical methods in Open Source Software research: Facts, trends and future directions

Open Source Software (OSS) is a field of study with increasing interest of researchers. By its nature, OSS is especially suitable for empirical research. A great number of OSS related empirical studies have been conducted, but no effort has been made to systematically review the published evidence. This paper presents the results of a systematic review to investigate research topics and used methods in OSS related research. We present our results as facts and trends in this field and provide directions for future research.

Inner Source--Adopting Open Source Development Practices in Organizations: A Tutorial

Inner source, the adoption and tailoring of open source development practices in organizations, is receiving increased interest. However, although it offers numerous benefits, many practitioners are unclear about what it is and how to adopt it. When adopting inner source, organizations should consider nine factors pertaining to product, process, and organization. A description of three inner-source initiatives illustrates these nine factors.