# User Security Measures ## Overview A number of measures have been taken to ensure the integrity and resilience of the deployed smart contracts. These measures are designed principally to ensure the safety of protocol assets, but also to ensure reasonable governance occurs. Below is a list of some, but not all, of the user security measures Ethena Labs has implemented across the deployed smart contracts. ## Measures 1. Inherited from the OpenZeppelin implementation of the battle-tested [ERC4626 Token Vault standard](https://ethereum.org/en/developers/docs/standards/tokens/erc-4626/). This enables users to have comfort that the protocol is inheriting audited & thoroughly used code throughout the space. 2. An unstake cooldown period where *sUSDe* tokens are immediately settled for *USDe*, but the staker cannot withdraw the *USDe* until the cooldown period has elapsed to prevent attacks in a single block. 3. Linear vesting of reward payments over 8 hours to prevent sandwich attacks where a user stakes immediately before and unstakes immediately after a reward payment at the expense of other stakers. 4. A minimum non-zero total *sUSDe* supply of 1 ether ($1 to start) to further prevent donation attacks beyond the protections the OpenZeppelin implementation provides. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.ethena.fi/solution-design/staking-usde/user-security-measures.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.