A society wide leaderboard that scrapes every member's competitive programming profile on a schedule and rebuilds the standings.

01 Architecture

• Django REST on PostgreSQL, with Celery and a Redis broker doing the work off the request path.
• A beat schedule fans out one scrape task per member every two minutes, rather than one long serial job.
• Results are chained into a single leaderboard rebuild, so standings are never assembled from partial data.
• React front end reading the materialised standings.

02 What is in it

• Standings are at most two minutes stale.
• One slow or failing profile cannot stall the whole refresh.
• Made practice visible, which is most of why people kept at it.