Borrow UNIT

In a joint, concurrent, two-transaction process, the user borrows additional UNIT stablecoins against their existing Bitcoin collateral. This increase in debt raises the Bitcoin price at which liquidation would be triggered.

The user initiates a transaction with their existing vault UTXO, requesting to borrow additional UNIT runes against their BTC collateral. The MPC Network verifies the vault's current collateralization ratio and the requested borrow amount to ensure it maintains the required safety margin. The transaction builder constructs a PSBT that updates the vault's borrowed amount while keeping the BTC collateral locked. The output includes the user receiving their additional UNIT runes and an updated vault UTXO reflecting the new borrowed amount.

In a second transaction, the updated vault state is processed, paying the network fees for both transactions to maintain atomicity. This generates an updated vault token recording the new borrowed amount and collateralization ratio. Like the original vault, the UTXO maintains both the user update path and the guardian/oracle liquidation path. An OP_RETURN output records the updated vault state including the new borrowed amount and collateral ratio.

Borrow UNIT Transaction Diagram