WETH / SWAMP
fee 0%- Swap WETH → SWAMPhook takes 2%
- Swap SWAMP → WETHhook takes 2%
- Add, then remove liquiditycame back whole
pool 0x50d5f080995afab5211bc0f17ab0bd4dc1a23e164ef001a73aaea0f9a07c4335
Reading the hook.
The address, the bytecode, then a swap each way through its pool. A few seconds.
13 pools use this hook, the first one 12 d ago.
The address enables before swap returns delta, after swap returns delta. The hook is allowed to take; the next two checks measure whether it does.
It takes 2% of each swap on top of the pool fee.
Liquidity added and removed in the same block came back whole.
A fixed fee of 0%, written in the pool key.
No owner and no admin functions found.
Not a proxy, no DELEGATECALL, no SELFDESTRUCT.
Each callback refused a call that did not come from the PoolManager.
13 pools over 11 days.
Measured at block 93,031,989. 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 0x50d5f080995afab5211bc0f17ab0bd4dc1a23e164ef001a73aaea0f9a07c4335
pool 0x3f2cf029f395ad71a8d5f59c01b89a660a52eacced2e884505ccf81ac7461be1
Selectors found in the dispatcher, named from the public signature database. Red ones are what an owner usually keeps for itself.