> For the complete documentation index, see [llms.txt](https://docs.stroom.network/stroom/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.stroom.network/stroom/smart-contracts/wstrbtc-erc-4626-wrapper.md).

# wstrBTC ERC-4626 Wrapper

**`wstrBTC` is an ERC-4626-compliant wrapper** for `strBTC`, designed to ensure compatibility with DeFi protocols that require non-rebasing, fixed-balance tokens. While `strBTC` leverages a rebasing mechanism to reflect yield directly in user balances, many DeFi platforms are not optimized to support rebasing assets. `wstrBTC` solves this by wrapping `strBTC` into a standard vault interface, allowing users to deposit `strBTC` and receive a fixed-amount `wstrBTC` token in return. This enables seamless participation in DeFi applications such as lending markets, yield aggregators, and collateralized protocols. Internally, `wstrBTC` accrues yield through changes in its exchange rate relative to `strBTC`, preserving the underlying yield dynamics while maximizing composability and protocol compatibility.