TL;DR — In-Game Economy

Design an in-game economy system for a multiplayer game with millions of players. The system manages virtual currencies (premium purchased with real money, soft earned through gameplay), a player-to-player marketplace for trading items, and an item shop with rotating inventory and limited-edition drops. Key features: Virtual currency management: premium (purchased) and soft (earned) currencies. Player-to-player marketplace with listing, buying, and bidding.