PrivyFlow

PrivyFlow is a dark pool DEX built on Uniswap v4 that eliminates MEV extraction through cryptographic commitments. Users commit to swap amounts using keccak256 hashes without revealing trade details, then execute after a mandatory 10-block delay (~2 minutes) that prevents frontrunning and sandwich attacks. The system utilizes a specialized DarkPoolHook with the BEFORE_SWAP flag that intercepts transactions to verify commitments on-chain before allowing settlement through the Uniswap v4 PoolManager. Liquidity providers can add concentrated or full-range liquidity to ETH/USDC pools with customizable fee tiers (0.01%-1%), while traders enjoy hidden amounts and protected execution. The commit-reveal scheme ensures that bots cannot extract value from pending transactions since amounts remain encrypted until the reveal phase, after the privacy delay has passed.

The project uses Solidity 0.8.26 with Foundry for smart contract development, deploying three core contracts to Sepolia: CommitStore (manages commitments and enforces 10-block delays), DarkPoolHook (Uniswap v4 hook with BEFORE_SWAP flag 0x04 for validation), and SwapRouter (handles settlement). The frontend is built with React 18, TypeScript, and Vite, styled with Tailwind CSS, and uses Wagmi/Viem for blockchain interactions. The commit-reveal flow generates client-side salts, computes keccak256(commitment, amount, minOut, salt), and stores commitments locally until the reveal phase. We integrated Reown AppKit for wallet connection and used Uniswap v4's PoolManager for actual swaps. A particularly hacky aspect was handling the pool initialization check—since Uniswap v4 reverts when querying non-existent pools, we implemented error-state detection in Wagmi with retry: false to distinguish between uninitialized pools and non-existent ones, routing users accordingly without infinite loading states.