一句话：通过 86 个开源项目的提交时间戳首次大规模实证刻画软件工程师的工作时段，发现多数人遵循典型办公时间。
异常工作时间会损害健康、幸福感和生产力，但此前缺乏对软件工程师实际工作模式的大规模实证刻画。本文分析 86 个大型开源项目的提交时间戳，涵盖受雇与志愿开发者，以建立可用于压力与过载检测的工作模式基线。研究发现，三分之二的软件工程师主要遵循典型办公时间（10 点至 18 点），通常不在夜间和周末工作，但项目与个体间差异很大。研究未支持项目成熟会减少异常工时的假设。Firefox 案例表明，受雇开发者更多在办公时间工作，而资历（提交次数或职位）不影响工作时间。作者认为，基于工时或工作产物时间戳进行压力检测，需要建立个体层面的基线。
Abnormal working hours can reduce work health, general well-being, and productivity, independent from a profession. To inform future approaches for automatic stress and overload detection, this paper establishes empirically collected measures of the work patterns of software engineers. To this aim, we perform the first large-scale study of software engineers' working hours by investigating the time stamps of commit activities of 86 large open source software projects, both containing hired and volunteer developers. We find that two thirds of software engineers mainly follow typical office hours, empirically established to be from 10h to 18h, and do not usually work during nights and weekends. Large variations between projects and individuals exist. Surprisingly, we found no support that project maturation would decrease abnormal working hours. In the Firefox case study, we found that hired developers work more during office hours while seniority, either in terms of number of commits or job status, did not impact working hours. We conclude that the use of working hours or timestamps of work products for stress detection requires establishing baselines at the level of individuals.