A leaderboard with a scheduled reset
Rank from a summary table rather than the raw ledger, snapshot the winners before you clear, and pay from the snapshot.
Engagement and Content
Leaderboards, achievements, contests, provably fair draws and announcements.
6 entries
A provably fair draw anyone can verify
Commit to a server seed before the draw, publish it after, and let any user reproduce the result themselves. The scheme, and the mistake that makes it worthless.
Achievements that reward the behaviour you want
A table of conditions, a checker that runs after activity, and a unique key so an achievement can only be awarded once.
A daily task list that resets cleanly
Generate the day's tasks once, track progress against a date key, and pay the completion bonus exactly once — no midnight cron required.
A shoutbox that does not become a spam channel
Rate limited, length capped, link stripped, moderatable, and cheap to poll. The five constraints that keep a chat box usable.
Run a contest without paying the prize twice
Snapshot the standings, pay from the snapshot, mark the contest closed — all in one transaction, with the entry rules decided before it opens.