Reading the hook.
The address, the bytecode, then a swap each way through its pool. A few seconds.
v4 hook · Robinhood Chain · block 92,975,511
0x81bF…A8CC
The eight checks
18 pools use this hook, the first one 106 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 1.20% 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 0x4e59b44847b379578588920cA78FbF26c0B4956C. Owner-style functions: withdrawPendingEth, 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 record18 pools over 106 days.
Measured at block 92,975,511. 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 & 0x3fff0x28cc · 10100011001100
- 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 / LIFE
fee dynamic, now 0%- Swap ETH → LIFEhook takes 1.19%
- Swap LIFE → ETHhook takes 1.20%
- Add, then remove liquiditycame back whole
pool 0xf35d10671f51b57d89dfcfc677d23926c44a3f654e6ec598e0cb907240cf0dca
ETH / ECHO
fee dynamic, now 0%- Swap ETH → ECHOhook takes 1.19%
- Swap ECHO → ETHno liquidity above the price
- Add, then remove liquiditycame back whole
pool 0x17a3a3b575bbcdf21c33608d1e5ecdad4ecce6015fe5a4426a583ed5c7cdd594
Read from the bytecode
- Code size
- 16,295 bytes
- Owner
- 0x4e59b44847b379578588920cA78FbF26c0B4956C
- Proxy
- no
- DELEGATECALL
- absent
- SELFDESTRUCT
- absent
- Outside calls
- 28
- 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.
- 0x037aadbe getPoolConfig
- 0x07ef2190 poolConfigs
- 0x1accff55 withdrawPendingEth
- 0x1c75f085 teamAddress
- 0x21d0ee70 beforeRemoveLiquidity
- 0x259982e5 beforeAddLiquidity
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 add liquidity. Can refuse a deposit, or only let some addresses provide liquidity.
- 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.