ERC1967Proxy

What it can do to your swap

• Its code can be replacedThe hook is a proxy (EIP-1967). Whoever controls it can swap in new code, so what it does today is not a promise for tomorrow.
• Can take a fee from your outputAfter the pool fills your swap, the hook can keep part of what you were about to receive.
• Can change the price you getBefore your swap runs, the hook can take or add tokens, so the amount you get is set by its code as well as the pool.
• Runs code before your swap and can block itThe hook is called before every swap. It can revert, which makes your swap fail.
• Runs code after your swap and can block itThe hook is called after every swap. It can revert, which undoes your swap.
• Can block people from adding liquidityCalled before each deposit into the pool.
• Runs code when a pool is createdCalled once, when someone creates a pool with this hook.
• Can charge a different fee on each swapThe pool's LP fee is dynamic: the hook sets it, swap by swap.

Read from the hook address: flag bits beforeInitialize, beforeAddLiquidity, beforeSwap, afterSwap, beforeSwapReturnsDelta, afterSwapReturnsDelta. Flags glossary.

Last test swap

A quote for a tiny exact-in swap each way through ETH / ? with Uniswap's V4 Quoter, compared with the pool's mid-price minus its 0.00% LP fee. It is an eth_call: nothing is signed or spent. Probed 7 h ago, every hour.

Pools