SweepHook

A trading tax hook. It takes a cut of every trade, keeps rewards to claim and only works with its own launcher.

• Takes a cut of every trade

  On top of the normal pool fee, it keeps a share of every trade for itself.

  The code that does this (beforeSwap):

  function beforeSwap(address, PoolKey calldata key, SwapParams calldata params, bytes calldata)
      external
      onlyPoolManager
      returns (bytes4, BeforeSwapDelta, uint24)
  {
      PoolId id = key.toId();
      PoolInfo storage info = pools[id];
      if (!info.registered) revert PoolNotRegistered();
      bool specifiedIsZero = (params.amountSpecified < 0) == params.zeroForOne;
      if (!specifiedIsZero) return (IHooks.beforeSwap.selector, BeforeSwapDeltaLibrary.ZERO_DELTA, 0);
  
      uint256 base = params.amountSpecified < 0 ? uint256(-params.amountSpecified) : uint256(params.amountSpecified);
      uint256 side = (base * info.feeBps) / BPS;
      if (side == 0) return (IHooks.beforeSwap.selector, BeforeSwapDeltaLibrary.ZERO_DELTA, 0);
      uint256 total = side * 2;
      // exact-in: the swap proceeds with (input - fee); exact-out: the swap produces (output + fee) and we keep the fee
      poolManager.take(key.currency0, address(this), total);
      _credit(id, info, side);
      return (IHooks.beforeSwap.selector, toBeforeSwapDelta(int128(uint128(total)), 0), 0);
  }

• Rewards to claim

  It keeps track of rewards to be claimed later.

• Only its own launcher can use it

  New pools with this hook can only be created by its own factory or launcher.

  The code that does this (beforeInitialize):

  function beforeInitialize(address sender, PoolKey calldata key, uint160)
      external
      view
      onlyPoolManager
      returns (bytes4)
  {
      if (sender != factory) revert NotFactory();
      if (!pools[key.toId()].registered) revert PoolNotRegistered();
      return IHooks.beforeInitialize.selector;
  }

• Anyone can trigger payouts

  Anyone can claim what they’re owed, so nobody has to wait on the hook developer.

  The code that does this (claim):

  function claim() external returns (uint256 amount) {
      amount = pending[msg.sender];
      if (amount == 0) return 0;
      pending[msg.sender] = 0;
      totalPending -= amount;
      _payEth(msg.sender, amount);
      emit FeesClaimed(msg.sender, amount);
  }

Who controls it: The code itself can’t be changed. The hook developer can change: factory, treasury, rescue excess.

Based on the hook’s published code.