The Mastodon API could do with an expires_at option for posting non-poll statuses which are useless after a specific date (such as gig notifications, etc.)
(Akkoma/Pleroma support it as a custom extension but Mastodon/GotoSocial don’t seem to.)
(Obviously I can rig something up to remember what’s been posted in SQLite and delete/mark them expired when their time is up but it’d be easier if it was part of the general API.)