Sustainable Yield, Private Leverage.
Lend is a borrowing platform that allows users to use various assets as collateral to borrow Silk. There is a whitelist of tokens that the protocol will accept as collateral. Each whitelisted token has an isolated deposit pool known as a Vault. The isolated deposit pools means that price movement in one of your Vaults will not impact the loans you have in other Vaults. In other words, you are allowed to take out multiple loans at once, but each loan can only be collateralized by a single token.
Each Vault also has its own Risk Parameters. These parameters are:
- Interest Rate: Annual interest rate charged on your loan. This value is listed as APR, not APY, and is approximately continuously compounded. Every time a user interacts with a Vault, the interest for all positions is compounded at the same time. Interest rates can be changed once per 7 days, and they can move by a maximum of 1% in either direction. Interest rates cannot be negative. Interest rates are controlled by the protocol.
- Borrowing Fee: A one-time fee assessed when you open your loan. Each Vault has a base borrowing fee, and there is an additional global borrowing fee that is based on the ratio of supply and demand for Silk. The exact mechanics of this will be explored in the Fees and Risks section of the documentation. Base borrowing fees for each vault can be changed once per 7 days, and they can move by a maximum of 1% in either direction. Borrowing fees cannot be negative. Borrowing fees are controlled by the protocol.
- Mint Cap: This is the maximum amount of Silk that can be borrowed from this Vault. This mechanism prevents Silk from being backed too heavily by a single form of collateral. This value is for the entire Vault -- a cap of 2,000,000 Silk means the sum of all loans from this Vault cannot exceed 2,000,000. It does not mean that each individual loan is capped at 2,000,000 Silk. Mint Caps can be raised and lowered by the protocol, but the Mint Cap can never be reduced below 0.
- Max LTV: This is the maximum loan-to-value ratio that the Vault allows for a loan. The more volatile the price of a collateral is, the lower the Max LTV will be. Positions that are above the Max LTV are marked for liquidation, which will be described below. Upon liquidation your loan will be repaid by external users and your collateral will be sold to them at a discount as compensation. Max LTVs can be changed by the protocol. Max LTV cannot ever be decreased on an existing Vault. This prevents the protocol from silently forcing liquidations on existing borrowers. Max LTVs can only ever be increased. If a Max LTV would ever have to be decreased, the Vault would be Deprecated, preventing new borrowing activity, and a new Vault would be created with the new Max LTV.
- Liquidation Discount: This is the percent discount that collateral is sold at when a position is liquidated. For example, if a Silk loan in an sSCRT vault is being liquidated and the price of sSCRT is $1, and the Liquidation Discount for that vault is 10%, then liquidators will be allowed to use Silk to purchase the borrower's sSCRT as $0.90. This is an incentive for liquidators to liquidate at-risk positions before they are underwater. The Liquidation Discount can be changed by the protocol at any time.