Design a Real-Time Leaderboard
Medium · System Design · about 45 minutes
Asked at Roblox, Amazon, Meta, Google, Bloomberg, D. E. Shaw.
Design a real-time leaderboard for an online game with 100M players. Scores update when matches finish (~10k updates per second, peaks of 50k). Anyone can see the top 100, and their own rank with the players around them, on daily, weekly and all-time boards, within a second of a score changing.