Reading the hook.
The address, the bytecode, then a swap each way through its pool. A few seconds.
v4 hook · Robinhood Chain · block 93,033,526
0x76F3…60Cc
The eight checks
16 pools use this hook, the first one 39 d ago.
- 01caution
Permissions that touch your moneyThe address enables before swap returns delta, 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 2.30% of each swap on top of the pool fee.
- 03pass
LPs can get outLiquidity added and removed in the same block came back whole.
- 04pass
The fee is the feeA fixed fee of 0%, written in the pool key.
- 05caution
No one holds the switchNo owner() but it has claim, claimable.
- 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 record16 pools over 39 days.
Measured at block 93,033,526. 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 & 0x3fff0x20cc · 10000011001100
- 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 / FEW
fee 0%- Swap ETH → FEWhook takes 2.30%
- Swap FEW → ETHhook takes 2.25%
- Add, then remove liquiditycame back whole
pool 0x65b6ed5aa1299a49ea95bff4fbb5eba6d015c40a704a7cbb20253adb3c8c3265
ETH / FEW
fee 0%- Swap ETH → FEWhook takes 1.00%
- Swap FEW → ETHno liquidity above the price
- Add, then remove liquiditycame back whole
pool 0x69d3517e1c7469b79d7b9467a0b7609d533324572f3ada99a0c72cd5c8d3db63
Read from the bytecode
- Code size
- 11,289 bytes
- Owner
- none found
- Proxy
- no
- DELEGATECALL
- absent
- SELFDESTRUCT
- absent
- Outside calls
- 5
- 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.
- 0xdc98354e beforeInitialize
- 0xe170a462 claim
- 0xe1b4af69 afterDonate
- 0xf92f23a7 accrued
- 0xc4e833ce getHookPermissions
- 0xd55be8c6 MAX_FEE_BPS
- 0xdc4c90d3
bit 4
After donate
bit 3Before swap returns deltabit 2After swap returns deltabit 1After add returns deltabit 0After remove returns delta- Before initialize. Runs once, when a pool is created.
- Before swap. Runs before every swap. On a dynamic-fee pool it can set the fee each time.
- After swap. Runs after every swap.
- Before swap returns delta. Can take part of what you put into a swap, or change how much is swapped.
- After swap returns delta. Can take part of what you get out of every swap.
poolManager
0xb1a25c94 creatorShareBps0xb47b2fb1 afterSwap0xb6a8b0fa beforeDonate0xc45a0155 unknown0x91dd7346 unlockCallback0x9f063efc afterAddLiquidity0xad091230 launches0x66ef208f MAX_EXTRA_FEE_BPS0x6c2bbe7e afterRemoveLiquidity0x6fe7e6eb afterInitialize0x7eb9835f MAX_GUARD_SECONDS0x348f14ba guardSeconds0x575e24b4 beforeSwap0x61d027b3 treasury0x259982e5 beforeAddLiquidity0x2e397572 MIN_CREATOR_SHARE_BPS0x3137c05d unknown0x0cfb82dd claimable0x21d0ee70 beforeRemoveLiquidity0x24a9d853 feeBps