Introduction
In FAANG interviews, aspiring product managers are often tested on their ability to design complex systems. One challenge that candidates might face is designing the architecture for a technology-based product, like a mobile application. In this blog post, we will tackle the question, “Design system architecture for a peer-to-peer chess mobile application.” We will provide an insightful walkthrough on how to utilize structured frameworks, as outlined in the book ‘Decode and Conquer: Answers to Product Management Interviews,’ for structuring a robust answer.
Detailed Guide on Framework Application
Selecting a Framework
The DIGS Method™ (Diagram, Interfaces, Goals, Steps) is well-suited for system architecture design questions. It helps visualize components and their interactions while focusing on user goals and functional steps.
Step-by-Step Guide Using DIGS
The DIGS Method™ consists of:
- Diagram: Draw a high-level block diagram representing the main components of the system. For the chess app, include user interfaces, game logic, network connections, databases, and notifications.
- Interfaces: Describe the interfaces between components. Discuss APIs for client-server communication, protocols for peer-to-peer interactions, and database access patterns.
- Goals: Define the goals of the system. For a chess app, goals may include low latency play, high availability, scalability to handle many users, and data integrity for game states.
- Steps: Enumerate the steps for common operations, like starting a new game, making a move, or handling disconnections.
Hypothetical Example Application
Begin with the diagram, visualizing how the mobile clients connect to a backend server for matchmaking and to a peer-to-peer network for gameplay. Discuss RESTful APIs for account services and WebSocket protocols for real-time game communication. Define goals around delivering seamless gameplay experience even on weak network conditions, supporting thousands of concurrent games, and safeguarding against cheating. Elaborate on steps, including queuing systems for pairing players and state management for recovering games if a player disconnects.
Facts Checks
While candidates may not know specifics about network protocols or database scaling, they can use industry standards like HTTP/2 for efficient communication or distributed databases like Cassandra for scalability. Drawing from common practices helps provide a plausible architecture that would be expected in a real-world scenario.
Effective Communication Tips
When discussing the architecture, use clear language and, if possible, visual diagrams. Relate each component back to the user goals and provide rationale for your design choices. As you step through the operations, ensure your explanations showcase a user-centered design mindset and technical acuity.
Conclusion
Designing system architecture requires both creative and logical thinking. Applying the DIGS Method™ provides a structural approach that aligns your design process with user goals and system requirements. Practicing this framework will sharpen your skills for FAANG interviews, as you articulate a compelling vision for a peer-to-peer chess mobile application’s architecture.