A mod for the game Factorio, adding seasonal changes to the length of the day.
The base game has the day split into 50% daytime, 40% dawn/dusk, 10% night. The default settings for this mod alter that on a 30-day cycle, with the shortest daytime being 20% and the longest 70%. Winter has long nights and summer has dusk transitioning to dawn with no full darkness at all.
Also exposes an option to make game days longer or shorter.