This report describes RoSSMa and it's development process, a software designed to ease the management of rotation shift schedules for Helsetjenestens Driftorganisasjon. As a replacement solution, it needs to e ectively ful ll everything the current implementation can accomplish, in which schedules are organized in highly advanced excel sheets. Rotating shift schedules are used in certain professions to ensure that their critical posi- tions stay manned at every hour of the day, while ensuring that employees don't exceed the laws and regulations regarding appropriate durations of work schedules. It's accom- plished by categorizing each day into clearly de ned shifts which each last for a speci c duration of hours, which are distributed into di erent types of weeks that are assigned to employees. These weeks are rotated between the participants each week, resulting in a di erent work pattern nearly every week. It's therefore critical to be able to review this schedule easily and hassle free. The solution was made web-based to take accessibility concerns into consideration, which is of substantial importance. The backbone of the software is developed in PHP as a result, so that the data can be accessed in HTML format by traditional browsers. The report is an in-depth look into the software, it's features and how they are imple- mented. It also describes the development process and the thought process regarding important decisions.