Pretty much a new version of a previous spin-off game that allows you to use new design options in the main game, which is actually a pretty decent way to do paid DLC for Animal Crossing.

It suffers slightly from AC's already pretty unwieldy menus and classic unnecessary Nintendo rigidity on how some items can and can't be placed but there's something really quite calming about taking on a new housing assignment every few days. There's good variation in the themes given to you while items and feature unlocks are doled out at a decent rate, allowing you to do your own thing and also update previous builds as you unlock more.