> For the complete documentation index, see [llms.txt](https://docs.bitsong.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.bitsong.io/features-and-modules/upgrade.md). # Upgrade Upgrade is an implementation of a Cosmos SDK module that facilitates smoothly upgrading a live Cosmos chain to a new (breaking) software version. It accomplishes this by providing a `BeginBlocker` hook that prevents the blockchain state machine from proceeding once a pre-defined upgrade block height has been reached. The module does not prescribe anything regarding how governance decides to do an upgrade, but just the mechanism for coordinating the upgrade safely. Without software support for upgrades, upgrading a live chain is risky because all of the validators need to pause their state machines at exactly the same point in the process. If this is not done correctly, there can be state inconsistencies which are hard to recover from. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## 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.bitsong.io/features-and-modules/upgrade.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.