Reading the hook.
The address, the bytecode, then a swap each way through its pool. A few seconds.
v4 hook · Robinhood Chain · block 93,457,977
0x4674…20Cc
The eight checks
1 pool use this hook, the first one 21 h 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 1.00% 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 transferFrom, transfer, 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.
- 08caution
Track record1 pool, first seen 0 days ago.
Measured at block 93,457,977. 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 / FIXLANTERN
fee 0%- Swap ETH → FIXLANTERNhook takes 1%
- Swap FIXLANTERN → ETHhook takes 1.00%
- Add, then remove liquiditycame back whole
pool 0x97f8abd24a4c8764599771544369914fc800a476d101e6e24eedfb6d45db608c
Read from the bytecode
- Code size
- 7,330 bytes
- Owner
- none found
- Proxy
- no
- DELEGATECALL
- absent
- SELFDESTRUCT
- absent
- Outside calls
- 4
- 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.
- 0x03ee438c metadataURI
- 0x06fdde03 name
- 0x095ea7b3 approve
- 0x0abb0df7 hatched
- 0x0cd6cf82 SPACING
- 0x18160ddd totalSupply
- 0x21d0ee70 beforeRemoveLiquidity
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.
0x23b872dd
transferFrom
0x259982e5 beforeAddLiquidity0x26c671c2 tollBps0x313ce567 decimals0x3e0dc34e poolId0x481c6a75 manager0x4b0a1562 tollPaidOut0x4fc87301 nucleus0x575e24b4 beforeSwap0x6c2bbe7e afterRemoveLiquidity0x6fe7e6eb afterInitialize0x70a08231 balanceOf0x715018a6 renounceOwnership0x8a844687 keeperOf0x8da5cb5b owner0x91dd7346 unlockCallback0x95d89b41 symbol0x9f063efc afterAddLiquidity0xa9059cbb transfer0xb47b2fb1 afterSwap0xb49683ee creditBps0xb6a8b0fa beforeDonate0xbc234eb7 hookPermissions0xc4e833ce getHookPermissions0xc50497ae SUPPLY0xdc98354e beforeInitialize0xdd62ed3e allowance0xe0ba9436 jar0xe1b4af69 afterDonate0xecc35230 tollCollected0xf2fde38b transferOwnership0xf4b15ed7 drain