> For the complete documentation index, see [llms.txt](https://ketro.gitbook.io/ketro-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://ketro.gitbook.io/ketro-docs/lending.md). # Lending ### The pool One pool, denominated in pUSD, lending against many isolated positions. It is a standard **ERC-4626 vault**: deposit pUSD, receive shares, the exchange rate grows as borrowers pay interest. There is no lock-up and no permission — the vault is directly composable with ERC-4626 consumers such as Yearn v3 or Beefy. ### Where the yield comes from Borrowers pay a utilization-based rate: * 2% APR base * +8% APR pro rata up to the 80% utilization kink * +100% APR beyond the kink — a deliberate penalty band that pulls utilization back by pricing marginal borrowing out Lenders receive the borrow rate × utilization, minus a 15% protocol fee on interest. Idle liquidity earns nothing — it is what keeps a withdrawal available. ### What a lender takes on If a collateral position becomes worthless faster than the loan against it can be closed, the shortfall is borne by the pool. This is the ordinary failure mode of lending against a binary outcome, not an edge case — conservative LTV and the early-close ramp reduce it; nothing removes it. Withdrawal requires free liquidity. Funds currently lent out cannot be withdrawn until repaid, and nothing forces an early repayment for a withdrawal's convenience. --- # 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, and the optional `goal` query parameter: ``` GET https://ketro.gitbook.io/ketro-docs/lending.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. 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.