Reading the hook.
The address, the bytecode, then a swap each way through its pool. A few seconds.
v4 hook · Robinhood Chain · block 93,061,824
0x66bC…00c4
The eight checks
10 pools use this hook, the first one 56 d ago.
- 01caution
Permissions that touch your moneyThe address enables after swap returns delta. The hook is allowed to take; the next two checks measure whether it does.
- 02caution
What it takes from a swapIt takes 2% of each swap on top of the pool fee.
- 03pass
LPs can get outLiquidity added and removed in the same block came back whole.
- 04caution
The fee is the feeIts pools use a dynamic fee that the hook sets before every swap. It stands at 0% now and can change.
- 05caution
No one holds the switchOwned by 0x29ADc1aD15d2a32645Cca1429E4281376a14cBBf. Owner-style functions: setDefaultFee, setGasThreshold, withdraw, transferOwnership.
- 06pass
The code cannot changeNot a proxy, no DELEGATECALL, no SELFDESTRUCT.
- 07pass
Only the PoolManager can call itEach callback refused a call that did not come from the PoolManager.
- 08pass
Track record10 pools over 55 days.
Measured at block 93,061,824. A hook with an owner or a dynamic fee can behave differently later; scan again before a large trade.
What the address allows
A v4 hook's permissions are the last fourteen bits of its address. The PoolManager calls only what they switch on.
address & 0x3fff0x00c4 · 00000011000100
- bit 13Before initialize
- bit 12After initialize
- bit 11Before add liquidity
- bit 10After add liquidity
- bit 9Before remove liquidity
- bit 8After remove liquidity
- bit 7Before swap
- bit 6After swap
- bit 5Before donate
What it did to a real swap
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.
ETH / HIMS
fee dynamic, now 0%- Swap ETH → HIMShook takes 2.00%
- Swap HIMS → ETHhook takes 1%
- Add, then remove liquiditycame back whole
pool 0x23ffb2f6126149f20d3cfe219dfc1ed4b9ea8aaeac8a75f9b9d8edfba65676f2
ETH / HIMS
fee dynamic, now 0%- Swap ETH → HIMShook takes 2%
- Swap HIMS → ETHhook takes 1%
- Add, then remove liquiditycame back whole
pool 0xa2176bf0e57558d7a3fec161d110a270e1ca45330824cdb3b7d1da40e5042528
Read from the bytecode
- Code size
- 5,913 bytes
- Owner
- 0x29ADc1aD15d2a32645Cca1429E4281376a14cBBf
- Proxy
- no
- DELEGATECALL
- absent
- SELFDESTRUCT
- absent
- Outside calls
- 3
- Callbacks open to anyone
- none
Its functions, uncensored
Selectors found in the dispatcher, named from the public signature database. Red ones are what an owner usually keeps for itself.
- 0x08ac6289 tierTwoFee
- 0x1d9e182f unknown
- 0x21d0ee70 beforeRemoveLiquidity
- 0x259982e5 beforeAddLiquidity
- 0x330adf21 unknown
- 0x38759da4 gasThreshold
bit 4
After donate
bit 3Before swap returns deltabit 2After swap returns deltabit 1After add returns deltabit 0After remove returns delta- Before swap. Runs before every swap. On a dynamic-fee pool it can set the fee each time.
- After swap. Runs after every swap.
- After swap returns delta. Can take part of what you get out of every swap.
0x3a0d5443
setDefaultFee
0x408ce93b unknown0x4bab632f unknown0x575e24b4 beforeSwap0x5a6c72d0 defaultFee0x5f40ae9f unknown0x6c2bbe7e afterRemoveLiquidity0x6fe7e6eb afterInitialize0x79ba5097 acceptOwnership0x87df06dc clearPoolFeeOverride0x88457c34 poolFeeOverride0x8da5cb5b owner0x94168af8 swapCount0x9a50c628 tierOneFee0x9c14f085 unknown0x9d951b3b tierThreeFee0x9f063efc afterAddLiquidity0xaad33c17 unknown0xb47b2fb1 afterSwap0xb6a8b0fa beforeDonate0xbc063e1a MAX_FEE0xc4e833ce getHookPermissions0xcb3b3ab3 setGasThreshold0xcd34b7a8 unknown0xd9c87312 unknown0xd9caed12 withdraw0xdc4c90d3 poolManager0xdc98354e beforeInitialize0xe1a45218 BPS_DENOMINATOR0xe1b4af69 afterDonate0xe30c3978 pendingOwner0xf2fde38b transferOwnership