Latch

A real-time PvP wagering game powered by Solana.

Latch combines competitive multiplayer gameplay with blockchain-backed prize settlement. Players stake cryptocurrency, battle in real-time arenas, and receive automated payouts directly through Solana smart contracts.

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Why Latch?

Traditional online gaming platforms rely on centralized systems to manage entry fees, match outcomes, and rewards — players must trust the platform to handle funds fairly.

Latch addresses this by using blockchain technology for wager custody and payouts while keeping gameplay fast through a traditional game server architecture:

• Players maintain ownership of their funds until they enter a match
• Wagers are locked in a transparent on-chain escrow
• Match outcomes are validated by the authoritative game server
• Prize payouts are executed automatically through Solana smart contracts
• Players can verify all transactions directly on-chain

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What Does Latch Do?

Latch allows players to:

1. Connect a Solana wallet
2. Join or create a wager-based match
3. Deposit funds into a secure on-chain vault
4. Compete in a real-time multiplayer battle
5. Win the match and receive the combined prize pool

The platform combines the speed of modern multiplayer gaming with the transparency and security of blockchain settlement.

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Current Implementation

What's built

Layer	Status	Stack
Frontend game client	✅ Complete	Phaser 3, Vite
Multiplayer server	✅ Complete	Node.js, Express, Socket.io
Wallet authentication	✅ Complete	Solana Wallet Standard, Phantom, Backpack
User accounts	✅ Complete	PostgreSQL (NeonDB)
On-chain escrow & payouts	🔜 In progress	Solana, Anchor

Architecture

latch/
├── frontend/   Vite + Phaser 3 game client
└── server/     Express + Socket.io multiplayer server

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Running Locally

Prerequisites

• Node.js 18+
• A Solana wallet extension (Phantom or Backpack) set to Devnet
• A PostgreSQL database — NeonDB free tier works well

1. Server

cd server
npm install

Create server/.env (copy from .env.example):

DATABASE_URL=postgresql://user:password@host/dbname?sslmode=require
PORT=3001

node server.js
# → migrate: applied 001_create_users.sql
# → Server running on port 3001

2. Frontend

cd frontend
npm install
npm run dev
# → http://localhost:8080

Open a second browser tab to test multiplayer.

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How It Works

Step 1: Wallet Connection

Players connect a supported Solana wallet:

• Phantom
• Backpack
• Solflare
• Any Wallet Standard extension

The wallet serves as the player's identity and enables secure transaction signing. Extensions are auto-detected on page load — no manual selection needed if only one is installed.

Step 2: Authentication & Account

On first connect, players pick a unique username (3–20 alphanumeric characters). Username and wallet address are stored in PostgreSQL. Returning players are recognized automatically and skip straight to the game.

Step 3: Create or Join a Battle

A player can:

• Create a new battle with a chosen wager amount
• Join an existing battle created by another player

Once two players are matched, the battle begins.

Step 4: Deposit Wagers (in progress)

Before entering the arena:

• Each player deposits their wager
• Funds are sent directly to a Solana smart contract
• The smart contract locks the funds in a secure escrow vault

Neither player nor the backend can withdraw these funds during the match.

Step 5: Real-Time Combat

The game runs in the browser using Phaser 3 and communicates with the backend through WebSockets (Socket.io).

The backend acts as the authoritative game server:

• Synchronizes player positions and animations
• Validates combat events and applies damage
• Determines the final winner
• Broadcasts results to all players in the scene

Players are isolated by scene — only players in the same area interact.

Controls: arrow keys to move · Space to attack · T to chat

Step 6: Match Resolution (in progress)

When the battle ends:

• The backend verifies the winner
• A settlement request is triggered
• The Solana program validates the battle state

Only valid matches can be settled.

Step 7: Prize Distribution (in progress)

After successful validation:

• The entire prize pool is released from escrow
• Funds are transferred directly to the winner's wallet
• The transaction is recorded permanently on-chain

Players can independently verify the payout using a Solana explorer.

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Game Flow

Connect Wallet
       │
       ▼
Auth + Username Registration
       │
       ▼
Character Select
       │
       ▼
Create / Join Match
       │
       ▼
Deposit Wager  ← (in progress)
       │
       ▼
Real-Time Battle
       │
       ▼
Winner Determined (server-authoritative)
       │
       ▼
Smart Contract Settlement  ← (in progress)
       │
       ▼
Prize Sent To Winner

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System Architecture

Frontend

• Game rendering and player controls
• Wallet detection via Wallet Standard + legacy window.* injection
• Devnet verification via Solana JSON-RPC (no @solana/web3.js dependency)
• REST calls to server for user lookup / registration
• Real-time sync via Socket.io client

Tech: Phaser 3, Vite, Socket.io Client

Backend

• Authentication and user account management (PostgreSQL)
• Real-time game state, movement, and combat validation
• Scene-based player rooms — players only interact within the same scene
• SQL migrations applied automatically on boot

Tech: Node.js, Express, Socket.io, PostgreSQL (NeonDB)

Solana Program (in progress)

• Escrow management and vault accounts
• Battle state storage via PDAs
• Automated payout execution
• Refund handling for cancelled matches

Tech: Solana, Anchor Framework, Program Derived Addresses

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Security Design

On-chain escrow — Player funds are stored in program-controlled vault accounts, not backend wallets. No need to trust the platform with custody.

Wallet-based authentication — Users authenticate through cryptographic signatures. No passwords.

Server-authoritative gameplay — The backend validates all critical gameplay events to prevent cheating.

Transparent settlement — Every deposit, refund, and payout is verifiable directly on the Solana blockchain.

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Project Goal

Latch demonstrates how blockchain technology can be integrated into multiplayer gaming without sacrificing gameplay speed or user experience.

The project explores a model where:

• Competitive games become trust-minimized
• Prize pools are managed transparently
• Players retain visibility into how funds move
• Match outcomes can be settled securely and automatically

By combining real-time multiplayer infrastructure with Solana smart contracts, Latch creates a foundation for skill-based gaming with verifiable rewards.