I have once again given some thought to how we can realise this project. However, I realised that (in my opinion) we can’t start at all, because a Gantt view usually has a start and end date, whereas a deck card only has an end date. That means we should first make a PR where we can use the start date and end date for the views.
@biguenique, @derWalter @johnmaynard What do you think?
Edit: Linking Feature Request on Deck Repository: Add start date/time and duration to cards · Issue #6358 · nextcloud/deck · GitHub