Problem
Prevented race-condition data loss when many players submitted damage to the same boss concurrently.
Contribution
Owned the write path end-to-end — data model, implementation, tests.
Approach Show approach ↓ Hide approach ↑
Atomic DynamoDB conditional writes stop concurrent submissions from overwriting each other. Faction and member leaderboards run on Redis sorted sets — scores accumulate via zincrby, rank comes from zrevrank instead of scanning. Reward payouts run as Celery jobs across damage milestones, covered by unit tests.
Result
Eliminated the observed race-condition failure mode; leaderboards stay accurate under bursts of hundreds of writes per second.