Show HN: Derbyist – Up-to-date match calendar of football (soccer) derbies

If you follow soccer, you know that derbies are highly-charged matches between historically rival teams, usually local rivals. They are emotional and hard-fought matches that are great fun to watch, but while there are many online resources to find match schedules for different leagues, I could not find a resource with an always-updated list of upcoming derby matches. So I made one. Hope it's useful to you. Please let me know what you think.