TrueVoice

Human-verified reviews powered by World ID. Every review comes from a unique, Orb-verified human -- no fakes, no bots, no duplicates.

Built for ETHGlobal Cannes 2026 (World track).

Problem

Fake reviews cost the global economy $152B+ annually. AI makes traditional detection useless. TrueVoice uses World ID's proof of personhood to guarantee one person, one review per entity -- cryptographically enforced, on-chain recorded.

How It Works

1. Verify -- User proves they're a unique human via World ID (Orb level)
2. Review -- Rate 1-5 stars + write a text review (10-280 chars)
3. Record -- Review hash is stored on World Chain; full text in database
4. Enforce -- Same person cannot review the same entity twice (nullifier-based)

Tech Stack

Layer	Technology
Frontend	Next.js 16 (App Router) + Tailwind CSS v4
Identity	World ID via MiniKit SDK (@worldcoin/minikit-js)
Database	Turso / LibSQL (serverless SQLite)
Smart Contract	Solidity 0.8.24 (review hash registry)
Chain	World Chain (OP Stack, gasless)
Deployment	Vercel

Pages

• / -- Feed (latest verified reviews) + Places tab
• /write -- Write a review (select entity -> rate -> verify -> submit)
• /entity/[id] -- Entity detail with rating distribution and reviews
• /profile -- User profile with review history

Setup

pnpm install
cp .env.example .env.local
# Edit .env.local with your credentials
pnpm dev

Environment Variables

TURSO_DATABASE_URL=file:local.db        # Local dev (or Turso URL for prod)
TURSO_AUTH_TOKEN=                        # Turso auth token (prod only)
WLD_APP_ID=app_...                      # World Developer Portal app ID
WLD_ACTION=review                       # World ID action name
NEXT_PUBLIC_DEMO_MODE=true              # Skip World ID verification for testing

Seed Data

With the dev server running:

curl -X POST http://localhost:3000/api/seed

This creates 6 Cannes-local entities (restaurants, attractions, events) and 5 demo reviews.

Smart Contract

contracts/TrueVoice.sol -- Stores review hashes on-chain for immutability.

• submitReview(entityId, reviewHash, rating) -- Owner-only, called by trusted backend
• reviewExists(hash) -- Check if a review hash is recorded
• getAverageRating(entityId) -- On-chain average (x100 precision)

Deploy via Remix IDE to World Chain.

Architecture

World App (Host)
  |
  v
TrueVoice Mini App (WebView)
  |
  +-- MiniKit.verify()     --> World ID proof of personhood
  +-- MiniKit.walletAuth() --> Wallet-based session
  |
  v
Next.js API Routes
  |
  +-- POST /api/reviews    --> Verify proof, store review, submit hash on-chain
  +-- GET  /api/reviews    --> Fetch reviews (by entity or wallet)
  +-- GET  /api/entities   --> List entities
  |
  +---> Turso DB (full review text)
  +---> World Chain (review hash registry)

License

MIT