Funded Crossword

Real-time multiplayer crossword-style game with:

• Node.js + Express backend (backend/)
• PostgreSQL persistence
• SSE realtime updates
• React + Vite frontend (frontend/)

Tempo Mainnet: Defaults target Tempo Mainnet (chain 4217): MPP_TESTNET=false, TEMPO_RPC_URL=https://rpc.presto.tempo.xyz. The frontend uses viem’s tempo chain with the same RPC.

Tempo Moderato testnet (matches mppx testnet: true, chain 42431): set MPP_TESTNET=true, TEMPO_RPC_URL=https://rpc.moderato.tempo.xyz, and in frontend/src/wagmiConfig.ts use tempoModerato instead of tempo.

On-chain checks (TIP-20)

Payments use TEMPO_CURRENCY; winner payouts use the same token from WINNER_PAYOUT_PRIVATE_KEY. Verify RPC chain id and balances:

cd backend
npm run tempo:check

Project Structure

• backend/ - API server, game logic, DB schema/init
• frontend/ - web app UI (mobile-first responsive)

Prerequisites

• Node.js 18+ (recommended)
• PostgreSQL running locally or remotely

Backend Setup

1. Copy env template and fill values:

cd backend
cp .env.example .env

2. Set at least:

• DATABASE_URL

3. Install and run:

npm install
npm run dev

Backend default URL: http://localhost:3001

Health check:

GET /healthz

Frontend Setup

1. Install and run:

cd frontend
npm install
npm run dev

Frontend default URL: http://localhost:5173

If needed, set API base URL in frontend env:

VITE_API_BASE=http://localhost:3001

Core API Endpoints

• GET /puzzles - list puzzles (?status=all|active|completed)
• POST /puzzles/create - create puzzle
• GET /puzzles/:id - fetch one puzzle
• POST /puzzles/:id/reveal - reveal a random unrevealed letter
• POST /puzzles/:id/guess - guess full answer or char+index
• GET /events/puzzles/:id - SSE realtime stream

Demo User Identity

For mutating actions, backend uses:

• x-user-address header (preferred), or
• user_address in request body, or
• fallback: demo-user

Frontend includes a user-id input to simulate multiplayer users.

Notes

• Inputs are normalized/validated to uppercase alphanumeric (with spaces where allowed).
• Completed puzzles display full answer for all users.
• Char guesses on already revealed positions are rejected.