TY - GEN A1 - Mauerer, Wolfgang T1 - Approaches to Ultra Long-Term System Maintenance T2 - Embedded Linux Conference Europe (Berlin), 2016 Y1 - 2016 UR - https://www.youtube.com/watch?v=SAbrQqSC61M ER - TY - GEN A1 - Mauerer, Wolfgang T1 - Socio-Technical Aspects of Long Term Embedded Systems Maintenance T2 - Embedded Linux Conference, April 4-6, 2016, San Diego Y1 - 2016 ER - TY - CHAP A1 - Ramsauer, Ralf A1 - Lohmann, Daniel A1 - Mauerer, Wolfgang ED - Wassermann, Tony T1 - Observing Custom Software Modifications: A Quantitative Approach of Tracking the Evolution of Patch Stacks T2 - Proceedings of the 12th International Symposium on Open Collaboration (OpenSym '16) N2 - Modifications to open-source software (OSS) are often provided in the form of "patch stacks" -- sets of changes (patches) that modify a given body of source code. Maintaining patch stacks over extended periods of time is problematic when the underlying base project changes frequently. This necessitates a continuous and engineering-intensive adaptation of the stack. Nonetheless, long-term maintenance is an important problem for changes that are not integrated into projects, for instance when they are controversial or only of value to a limited group of users. We present and implement a methodology to systematically examine the temporal evolution of patch stacks, track non-functional properties like integrability and maintainability, and estimate the eventual economic and engineering effort required to successfully develop and maintain patch stacks. Our results provide a basis for quantitative research on patch stacks, including statistical analyses and other methods that lead to actionable advice on the construction and long-term maintenance of custom extensions to OSS. KW - CADOS KW - collaboration KW - Linux KW - maintenance KW - patch stacks Y1 - 2016 U6 - https://doi.org/10.1145/2957792.2957810 SP - 1 EP - 4 PB - ACM CY - New York ER - TY - CHAP A1 - Mauerer, Wolfgang T1 - A Virtual Computing Platform for the Internet of Things T2 - Embedded Linux Conference (San Diego), 2016 Y1 - 2016 ER - TY - JOUR A1 - Joblin, Mitchell A1 - Apel, Sven A1 - Mauerer, Wolfgang T1 - Evolutionary trends of developer coordination: a network approach JF - Empirical Software Engineering N2 - Software evolution is a fundamental process that transcends the realm of technical artifacts and permeates the entire organizational structure of a software project. By means of a longitudinal empirical study of 18 large open-source projects, we examine and discuss the evolutionary principles that govern the coordination of developers. By applying a network-analytic approach, we found that the implicit and self-organizing structure of developer coordination is ubiquitously described by non-random organizational principles that defy conventional software-engineering wisdom. In particular, we found that: (a) developers form scale-free networks, in which the majority of coordination requirements arise among an extremely small number of developers, (b) developers tend to accumulate coordination requirements with more and more developers over time, presumably limited by an upper bound, and (c) initially developers are hierarchically arranged, but over time, form a hybrid structure, in which core developers are hierarchically arranged and peripheral developers are not. Our results suggest that the organizational structure of large projects is constrained to evolve towards a state that balances the costs and benefits of developer coordination, and the mechanisms used to achieve this state depend on the project’s scale. KW - Developer coordination KW - Developer networks KW - Software evolution Y1 - 2016 U6 - https://doi.org/10.1007/s10664-016-9478-9 VL - 22 IS - 4 SP - 2050 EP - 2094 PB - Springer ER -