Void

A provably fair, on-chain casino game built on Solana. Navigate through tiles, avoid death traps, and cash out your winnings. Inspired by death.fun.

How It Works

Players deposit SOL and navigate a randomly generated tile board. Each row contains one hidden "death tile" - hit it and you lose everything. Successfully navigate rows to multiply your stake. Cash out anytime or risk it all for higher multipliers.

The game is provably fair: death tile positions are determined by a server seed that's committed (hashed) before you play. After each round, you can verify that outcomes weren't manipulated.

Features

• On-chain deposits & withdrawals - SOL moves directly through Solana smart contracts
• Provably fair - SHA-256 commit-reveal scheme, verify any game session
• Real-time caching - Redis-backed game state for seamless gameplay
• Leaderboard - Track top earners

Contract Addresses

Network	Address
Casino Program (Devnet)	7eoY2tr9vaZEEjX1q64q3ovND5Erg9ZjK8CfujxDfh8p
Casino PDA	HbiPVZB2aUPxEz4V3GLy52jTfB3ChmBAj8hmjZun641t
Authority	CUcTGB5CyRhfh9jvVDZB734DG38XfZFX1a3L86FosSBu

Architecture

├── fe/              # Next.js frontend
│   ├── components/  # React components (tileboard, leaderboard, etc.)
│   ├── store/       # Zustand game state
│   └── services/    # API + on-chain interactions
│
├── BE/              # Express.js backend
│   ├── routes/      # deposit, withdraw, payouts, cache
│   ├── servicies/   # Redis caching layer
│   └── Db/          # MongoDB schemas
│
└── contract/        # Anchor smart contract (Solana program)
    └── programs/    # deposit, withdraw, payout instructions

Quick Start

Prerequisites

• Node.js 18+
• Rust + Solana CLI (for contract development)
• MongoDB
• Redis

Backend

cd BE
npm install
cp .env.example .env  # Configure your environment
npm run dev

Required env vars:

• SOLANA_RPC_URL - Devnet RPC endpoint
• CASINO_PROGRAM_ID - Deployed program ID
• SOLANA_AUTHORITY_PRIVATE_KEY - Authority keypair (JSON array format)
• MONGO_DB_URL - MongoDB connection string
• REDIS_URL - Redis connection string

Frontend

cd fe
npm install
npm run dev

Frontend runs on localhost:3000, backend on localhost:8001.

Smart Contract

cd contract
anchor build
anchor deploy --provider.cluster devnet

Game Mechanics

1. Deposit - Send SOL to casino PDA, credited to your user account
2. Play - Click tiles row by row, avoiding death tiles
3. Multipliers - Each successful row increases your potential payout (starts ~1.10x, grows ~1.18x per row)
4. Cash out - Withdraw anytime to lock in winnings
5. Death tile - Hit it and lose your stake + accumulated earnings

Provably Fair Verification

Each game session:

1. Server generates a random seed
2. SHA-256(seed) is committed before gameplay
3. Death tiles derived from SHA-256(seed + "-row" + rowIndex)
4. After round ends, seed is revealed - verify the commit matches

Visit /verify?sessionId=<id> to verify any session.

Tech Stack

• Frontend: Next.js 14, Tailwind CSS, Zustand, Solana Wallet Adapter
• Backend: Express.js, MongoDB, Redis
• Blockchain: Solana, Anchor Framework
• Deployment: Render (backend), Vercel-compatible (frontend)

API Routes

Endpoint	Description
POST /api/depositFunds/dp	Process deposit transaction
POST /api/withdrawFunds/wd	Process withdrawal
POST /api/payouts/	Payout winnings
POST /api/cache/tile	Cache tile selection
GET /api/leaderboard/	Fetch leaderboard

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Built for 100x Solana Hackathon