The best protocols grew
the way forests do —
from root systems no one sees.

function testReentrancy() public {
  // attacker deploys malicious receiver
  Attacker atk = new Attacker(vault);
  vm.expectRevert("ReentrancyGuard");
  atk.attack{value: 1 ether}();
}

// Before: naive ABI encoding
bytes calldata = abi.encode(
  addr, amount, nonce
); // 96 bytes, lots of zeros

// After: custom tight packing
bytes packed = abi.encodePacked(
  bytes20(addr),
  uint96(amount)
); // 32 bytes

function afterSwap(
  address sender,
  PoolKey calldata key,
  SwapParams calldata,
  BalanceDelta delta,
  bytes calldata
) external override returns (bytes4) {
  _updateOracle(key.toId(), delta);
  return BaseHook.afterSwap.selector;
}