How to Build a Turn-Based Digital Board Game with AWS
Space Traders is a multiplayer board game I built using AWS for the Game Builder Challenge. The game combines the strategic elements of trading games with space exploration, allowing 2-4 players to compete as space merchants on a hexagonal grid.
Published Nov 24, 2024
Space Traders is a digital board game where 2-4 players navigate a hexagonal grid of planets and space stations, competing to become the most successful space merchant. The game combines elements of classic trading games with modern multiplayer features.
Core Features:
- Hexagonal board with various planet types
- Resource trading between planets
- Player-to-player trading system
- Mission completion mechanics
- Random space events
- Achievement system
The game relies on several AWS services working together:
- DynamoDB: Stores game sessions, player data, and trading records
- AppSync: Handles real-time updates for player moves and trades
- Lambda: Processes game logic and event triggers
- Cognito: Manages player authentication
- API Gateway: Routes player actions
- Lambda: Validates moves and processes turns
- S3: Hosts game assets and resources
- CloudFront: Delivers assets with low latency
The hexagonal grid system, built with React, represents different space sectors. Each hex contains either a planet, space station, or special event space. The board state synchronizes across all players through AppSync subscriptions.
A state machine in DynamoDB tracks:
- Current player turn
- Available actions
- Resource states
- Trade proposals
- Event triggers
AppSync subscriptions ensure all players receive immediate updates about:
- Player movements
- Trade proposals
- Resource changes
- Random events
- Mission completions
Challenge: Maintaining consistent game state across multiple players Solution: Implemented optimistic updates with server validation through Lambda
Challenge: Managing complex trade negotiations between players Solution: Created a two-phase commit system using DynamoDB transactions
Challenge: Balancing event frequency and impact Solution: Implemented a weighted event system with cooldown periods
type Game { id: ID! players: [Player]! currentTurn: String! boardState: BoardState! status: GameStatus!}type Player { id: ID! position: Position! resources: [Resource]! credits: Int!}- Normalized data structure in DynamoDB
- Optimistic updates for player actions
- Transaction-based critical updates
- Cached frequently accessed data
- Architecture
- Keep game state normalized
- Use transactions for critical updates
- Implement retry mechanisms
- Plan for disconnections
- Development Process
- Start with core mechanics
- Add multiplayer features incrementally
- Test with various network conditions
- Monitor performance metrics
- Game Balance
- Resource prices: 10-20% fluctuation
- Mission rewards: scaled by difficulty
- Movement costs: balanced with rewards
- Event impact: limited to maintain fairness
Planned features include:
- AI opponents using Amazon Bedrock
- Tournament system using Step Functions
- Mobile support through AWS Amplify
- Enhanced analytics and leaderboards
Building a multiplayer board game with AWS provided valuable insights into real-time game development and cloud architecture. The serverless approach simplified scaling and maintenance, while services like AppSync made real-time features straightforward to implement.
For those joining the AWS Game Builder Challenge, consider starting with a turn-based game. The architecture is more manageable than real-time games, while still offering engaging multiplayer experiences.
This project demonstrates how AWS services can be combined to create engaging multiplayer experiences. The key is starting with solid fundamentals and iterating based on testing and feedback.