GameServerManager (GSM3) is a comprehensive, full-stack web application for deploying, configuring, and monitoring game servers. Built with a React + TypeScript frontend and a Node.js/Express backend, it provides a browser-based panel for managing the lifecycle of game instances (Minecraft, Terraria, Palworld, etc.), real-time terminal access via custom PTY integration, file management with chunked uploads, scheduled tasks, backup management, and network tunneling (EasyTier). The architecture is a monolithic web application with a clear separation of concerns, communicating via REST APIs and WebSockets (Socket.IO). It demonstrates strong engineering practices in security (tar path traversal prevention, credential redaction, secure PTY control channels) and data persistence (atomic writes, serialized mutation chains for instance state). While the UI is Chinese-first and configuration relies on JSON file storage, the codebase contains several genuinely reusable, well-crafted components that exhibit non-obvious skill and architectural rigor.