Roeshimi I let it run on a server of mine. It can listen to callbacks from bunq and then sync on-demand. So when I do a card payment (or if there is any other kind of event on my account), it will then start the syncing process automatically. You can also just do manual one-off syncs, though, if for some reason you can't or don't want to listen for the callbacks.
Works well, and not really complicated in the grand scheme of things, but probably too hard to setup for the average user. Hopefully this will change at some point.