LiqOS
Uniswap V4 Hook
An auction-based JIT liquidity rebalancer implemented as a custom Uniswap V4 hook — eliminates LPs manually chasing price.
01 · Requirement Analysis
Uniswap V3 concentrates liquidity so tightly that LPs must manually rebalance ranges as price drifts — a constant, error-prone chore. The brief: a transparent, automated mechanism that rebalances liquidity mid-trade without custodial loss.
02 · Architecture Discovery
Explored the V4 hook lifecycle (beforeSwap / afterSwap / afterModifyLiquidity) and the unlock-callback flash-accounting model. Settled on a per-swap auction held inside the hook, with transient storage (EIP-1153) recording net deltas only within a single swap.
03 · Software Architecture
Three collaborating modules: the hook contract (entry + delta accounting), an auction market (Dutch-price, JIT) that matches an incoming swap against live bids, and a router adapter that triggers the rebalance before settlement.
04 · Development Principles
Gas-aware deltas via transient storage rather than persistent SSTORE; flash-accounting ensures every borrow is repaid in the same unlock window; reentrancy and repay guards on every entry point; fuzz/invariant tests around the auction.
05 · Impact
LPs earn JIT fees without manual repositioning; swaps route against freshly rebalanced liquidity for tighter effective price; the design generalizes to any V4 pool with minimal added gas.