Turnstile.sol#L141
Ether transfer is done with Address.sendValue(_recipient, _amount); in the withdraw function, OZs Address.sol library is used
There is this warning in OZs Address.sol library. Accordingly, he used the Check-Effect-Interaction pattern in the project:
It would be best practice to use re-entrancy Guard for reasons such as complicated dangers such as view Re-Entrancy that emerged in the last period and the possibility of expanding the project and its integration with other contracts:
https://twitter.com/lmount_/status/1577307245276459011?t=XSvtIkum8nuzI8ZM7lfq-A&s=19
https://github.com/euler-xyz/euler-contracts/commit/91adeee39daf8ece00584b6f7ec3e60a1d226bc9
