# Overview The blockchain is immutable, and once a contract is deployed, you cannot change its code. This works fine for many applications that can deploy a new contract for every new version they create. Sadly, this isn't adequate for Phase's needs as a lot of info is stored in the contract itself and cannot be moved from contract to contract.\ \ We use proxies for almost everything in Phase to get around this issue. A proxy allows us to run any target contract code in the current contract's storage. This means we can deploy a contract once and upgrade its code in the future.\ \ This does have its downside, though, as all the code is upgradable, We have to safeguard and secure the protocol to a point so that a bad actor cannot change code instantly. One contract owned by a timelock will control all the proxies inside Phase. With this, every upgrade and code change has to go through a period where everyone can see them and act accordingly.\ \ Phase uses the following proxy patterns in its systems: * [Admin Upgradeable Proxy](/proxies/admin-upgradeable-proxy.md) * [Storage Upgradeable Proxy](/proxies/storage-upgradeable-proxy.md) * [Diamonds](/proxies/diamonds.md) --- # 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.phase.cash/proxies/overview.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.