Authentica

Inspiration

Fake reviews cost US businesses $152 billion annually and destroy trust in local commerce. We were inspired by World ID's proof-of-personhood technology and wanted to solve a real problem: giving businesses and consumers authentic local reviews they can actually trust.

What it does

Authentica is a mobile-first local business review platform where every review requires World ID verification. Users search West Lafayette businesses, read human-verified reviews with clear trust badges, and cannot post without biometric proof of personhood. No bots, no fake accounts, just real local feedback.

How we built it

• World MiniKit for seamless biometric identity verification
• Next.js full-stack architecture (mobile-first UI + API routes)
• Prisma + SQLite for type-safe database operations
• Google Places API for automatic business photos and location data
• Custom submission pipeline cryptographically chaining World MiniKit's zero-knowledge proofs to database mutations

Challenges we ran into

The biggest challenge was building a tamper-proof review pipeline. We had to ensure World MiniKit's ZK-proof payload was validated server-side before any database write, while keeping the UX completely seamless. Integrating the MiniKit modal flow with Next.js API routes required careful state management to prevent race conditions.

Accomplishments that we're proud of

• Production-grade World ID integration, reviews physically cannot be posted without valid proof of personhood
• Automatic business photo fetching creates rich listings without manual data entry

What we learned

World ID verification can be a feature, not friction when designed as a trust primitive from day one. The MiniKit SDK is powerful but requires careful server-side validation to prevent bypass attempts. Mobile-first review flows need to balance discoverability with conversion, our category filters + prominent "Review" CTAs hit the right balance.

What's next for Authentica

Business dashboard for owners to see verified review trends. Review "helpfulness" voting system (only verified humans can upvote). Native iOS/Android apps with push notifications for review replies. Partnerships with local chambers of commerce for verified business listings.

Built With

• minikit
• worldchain
• worldid