DeFi Infrastructure Engineer — building on-chain primitives for Uniswap V4
Production-grade hooks that run fully on-chain — no off-chain relayers, no keepers, no trusted intermediaries. Two live DApps shipped to Base and Unichain mainnet.
| Project | What it does | Live DApp | Chains | Tests |
|---|---|---|---|---|
| il-aware-limit-order-hook | Limit orders that become yield-bearing positions and rebate impermanent loss from accrued yield. UHI9 Hookathon submission. | il-aware-hook.vercel.app | Unichain | 53 / 53 ✅ |
| limit-order-hook-v4 | Fully on-chain limit orders for Uniswap V4, executed in afterSwap. |
limit-order-hook-v4.vercel.app | Base · Unichain | 38 / 38 ✅ |
Turns a passive limit order into a yield-bearing position and compensates the user for impermanent loss out of the yield it earns. Submitted to the UHI9 Hookathon (Impermanent Loss & Yield theme), live on Unichain mainnet.
- Oracle-free IL rebate — impermanent loss derived from
sqrtPriceX96deltas via a 2nd-order Taylor approximation;rebate = min(yield, IL). No external price feeds. - Yield routing — executed output is deposited into an ERC-4626 vault until claim.
- Orders as NFTs — every order is an ERC-721: composable and tradable on secondary markets.
- O(1) tick scanning — doubly-linked list of active ticks only; swap cost scales with populated ticks crossed, not range width.
- Anti-DoS execution — failed orders don't revert the swap: they emit and re-queue, with gas metering to avoid OOG.
- Flash accounting — atomic settlement via Uniswap V4 native accounting, no ERC-20 transfer overhead.
Stack: Solidity 0.8.26 · Uniswap V4 · OpenZeppelin (ERC-721 / ERC-4626) · Foundry · Next.js · wagmi v2 · viem · RainbowKit
Deployed: hook on Unichain → 0x8C19…d4CE
Production limit orders for Uniswap V4 with automated, gas-bounded execution triggered directly inside swaps. Live on Base and Unichain mainnet.
- Self-executing — orders fill in the
afterSwaphook as the pool crosses their tick. No keepers, no relayers. - O(1) tick buckets — doubly-linked list of populated ticks for constant-time lookup during execution.
- Anti-DoS, graceful execution — a failing order never bricks the swap path.
- Bounded gas — 5 BPS execution fee, gas-metered batch execution, 150k gas cutoff per swap.
- Audit-ready — documented scope and invariants for external review: AUDIT_SCOPE.md.
Stack: Solidity 0.8.26 · Uniswap V4 · Foundry · Next.js · wagmi v2 · RainbowKit
- Fully on-chain — execution lives in the contract, not in a bot. If it needs a keeper or a relayer to work, it isn't done.
- Gas as a hard constraint — bounded, metered execution paths; no unbounded loops on the swap hot path.
- Anti-DoS by design — one failing order must never brick the pool for everyone else.
- Test-first — full Foundry suites covering unit, integration, and adversarial paths before anything ships.
- Mainnet or it didn't happen — deployed, verifiable, with a live frontend.
- Contracts — Solidity · Foundry · Uniswap V4 · OpenZeppelin (ERC-721 / ERC-4626)
- Frontend — Next.js · TypeScript · wagmi v2 · viem · RainbowKit
- Chains — Base · Unichain · Arbitrum (upcoming)
- Ops — Gnosis Safe 2-of-3 · Vercel · GitHub Actions · Foundry CI
- 🌐 Portfolio — impetus82.github.io
- 💬 Telegram — @yurka_e
- ✉️ Email — egoshin_crypto@proton.me