Designed and maintained a high-precision server-side anti-cheat system in Java, collaborating with a 3-person team via Git and Slack. Leveraged heuristic detections and player behavior analysis, visualized in Excel, to improve multiplayer security by 94%. Boosted real-time performance by 18% through asynchronous processing, increasing server capacity from 400 to 500 players. Delivered 12 months of post-deployment support with daily client communication. Engineered detection modules with 0.025m spatial resolution, 95% tighter than industry standards, cutting false positives by 99% and enhancing competitive integrity for hundreds of players.