Requirements

Design a scalable Chess game capable of handling 1 million concurrent games, we need to focus on both the core functionality of Chess and the scalability aspects. Below are the detailed features required:

Standard Chess Rules Implementation:
- Piece Movement: Accurate movement rules for all pieces (Pawn, Rook, Knight, Bishop, Queen, King).
- Special Moves: Support for castling, en passant, and pawn promotion.
- Check and Checkmate Detection: Algorithms to detect check, checkmate, and stalemate conditions.
- Draw Conditions: Implement rules for draw situations (threefold repetition, the fifty-move rule, insufficient material).
Scalable Architecture:
- Efficient Data Structures: Use memory-efficient structures to handle a large number of game instances.
- Concurrency Management: Thread-safe operations to handle simultaneous games without conflicts.
- Resource Optimization: Implement the Flyweight pattern to minimize memory usage for identical objects.
Game Management:
- Game Lifecycle: Create, update, and terminate games efficiently.
- Player Management: Handle player sessions and their interactions with games.
- Move Validation: Ensure all moves are legal according to the game state.
Design Patterns Implementation:
- Utilize appropriate design patterns (Factory, Singleton, Observer, Strategy, Command, Flyweight) to create a maintainable and scalable codebase.
Persistence and State Management:
- Saving and Loading: Ability to persist game states to a database or in-memory data store.
- Undo/Redo Functionality: Implement command history for moves to allow undo/redo actions.
Algorithm Efficiency:
- Optimize algorithms for move validation and game state checks to ensure performance does not degrade with scale.

Solution

Will be Covered in Our LLD Course - http://interview.lldcoding.com/course/low-level-design-and-concurrency-machine-coding-course-360

Design (LLD) Chess Game - Machine Coding