How to have an instance listed on join-lemmy.org/instances?

Hi! I'm new to lemmy. I think the join-lemmy instances list is a great resource, though I've noticed that the instance I recently set up does not appear in the list. Is listing automatic, and in that case what should I do to make sure it appears? And if it's not automatic, who should we contact to request to be included in the list?

Thank you!