Veil

Inspiration

Traditional prediction markets force users to compromise their financial privacy, publicly exposing wallet balances, position sizes, and trading strategies on-chain. We built VEIL to prove that forecasting can be decentralized, transparent, and completely private using zero-knowledge proofs.

What it does

VEIL is a privacy-first prediction market platform powered by Midnight testnet and synced with live Polymarket data. It allows users to bet on real-world outcomes using ZK proofs, ensuring position sizes, account balances, and individual trades remain 100% confidential while outcome validity is verifiably guaranteed on-chain.

How we built it

• Smart Contracts & ZK Circuits: Written in Compact on the Midnight Network for private state transitions and zero-knowledge proof generation.
• Frontend: Built with Vite, React, and Vanilla CSS featuring an electric dark-mode interface and dynamic probability charts.
• Data & Caching: Supabase fast cache layer paired with background Vercel cron jobs for live Polymarket event ingestion and instant page loads (~0ms latency).

Challenges we ran into

• Managing low-latency client-side ZK proof generation without degrading UI responsiveness.
• Harmonizing real-time public market odds with encrypted, zero-knowledge private user states.
• Optimizing serverless production deployment on Vercel for Hobby-tier cron schedule compliance.

Accomplishments that we're proud of

• Seamlessly integrating live Polymarket feeds into a privacy-preserving Midnight ZK environment.
• Delivering a state-of-the-art UI with robust guest browsing and strict session-gated betting.
• Achieving instant market lookups via a hybrid Supabase local caching architecture.

What we learned

• How to architect zero-knowledge smart contracts in Compact that separate public market data from private user balances.
• Best practices in client-side ZK proof UX—keeping users informed while cryptographic proofs compile in the background.

What's next for Veil

• Midnight Mainnet Deployment: Transitioning from testnet to live Midnight production circuits.
• AI Automated Oracles: Integrating decentralized LLM oracle networks for instant, dispute-free market resolutions.
• Mobile PWA & Embedded Wallets: Bringing one-tap private forecasting to mobile web browsers worldwide.

Built With

• midnight
• react
• supabase
• vanillacss
• vercel
• vite
• zk-proof