How many pomodoros do professional engineers need to complete a microtask of programming?

Microtask programming enables software engineers such as freelancers and part-time employees to contribute to software projects even when they can not spend much time on them. It decomposes software design into small, self-contained specifications. The decomposed specifications enable them to complete implementation and review task in a short time. In this paper, we empirically investigate the time required for software engineers to complete microtasks in an industrial setting and explore their perceptions of microtask programming by investigating two industrial projects using it. The projects were carried out in different companies and differed in the employment of the engineers. One contracted 9 freelancers, and the other asked for 8 part-time contributions from employees at work on other projects. We conducted a survey and a focus group with the engineers. Based on the development data of the case studies, we found that almost all microtasks were completed in less than four pomodoro repetitions, namely about two hours in the pomodoro technique. These data shows that engineers who cannot work full-time on a project can undertake microtasks if they can spare one-third of their work day. We also examine how engineers who are employees experience microtask programming similarly and differently from freelancers.