WETH / BEAR
fee 1%- Swap WETH → BEARnothing taken
- Swap BEAR → WETHnothing taken
- Add, then remove liquiditycame back whole
pool 0xf3e0bc98e90afe88f6adf698c4ab63be55637731d63168440db8a2788013d01c
Reading the hook.
The address, the bytecode, then a swap each way through its pool. A few seconds.
11 pools use this hook, the first one 11 d ago.
The address enables after swap returns delta. The hook is allowed to take; the next two checks measure whether it does.
A swap through it pays the pool fee and nothing else.
Liquidity added and removed in the same block came back whole.
A fixed fee of 1%, written in the pool key.
No owner() but it has setFactory, setAdmin.
Not a proxy, no DELEGATECALL, no SELFDESTRUCT.
Each callback refused a call that did not come from the PoolManager.
11 pools over 10 days.
Measured at block 93,059,681. A hook with an owner or a dynamic fee can behave differently later; scan again before a large trade.
A v4 hook's permissions are the last fourteen bits of its address. The PoolManager calls only what they switch on.
A small swap each way and a liquidity round trip, run through the PoolManager and this hook inside a call that is never sent. The pool fee is expected; anything else missing is the hook.
pool 0xf3e0bc98e90afe88f6adf698c4ab63be55637731d63168440db8a2788013d01c
pool 0xda9e92b1dfa791a8db75ca89cb5c2cef923c3ac4914cb06d74af2041c9747014
Selectors found in the dispatcher, named from the public signature database. Red ones are what an owner usually keeps for itself.