BCredit Contract Reference

The BCredit contract handles borrowing and leverage operations. It enables 0% interest loans backed by BLV and non-liquidatable leverage positions.

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Contract: BCredit.sol Version: Latest License: AGPL-3.0-only

Overview

BCredit provides two main capabilities:

Borrowing : Take loans against bToken collateral at BLV
Leverage : Create multiplied positions through borrow + buy loops

All positions are non-liquidatable because collateral is valued at BLV (guaranteed floor).

Borrowing Functions

borrow

Borrow reserves against bToken collateral.

function borrow(
  BToken _bToken,
  address _user,
  uint256 _collateralAmount,
  uint256 _borrowAmount
) external returns (uint256 fee_)

Parameter	Type	Description
`_bToken`	`BToken`	The bToken collateral
`_user`	`address`	User borrowing
`_collateralAmount`	`uint256`	bTokens to lock as collateral
`_borrowAmount`	`uint256`	Reserves to borrow

Returns:

fee_: Origination fee charged

Requirements:

Collateral must support the borrow amount at BLV
User must have approved bToken transfer

repay

Repay borrowed reserves and unlock collateral.

function repay(
  BToken _bToken,
  address _user,
  uint256 _collateralAmount,
  uint256 _repayAmount
) external

Parameter	Type	Description
`_bToken`	`BToken`	The bToken collateral
`_user`	`address`	User repaying
`_collateralAmount`	`uint256`	Collateral to unlock
`_repayAmount`	`uint256`	Debt to repay

Errors:

BCredit_RepaidMoreThanDebt: Repaying more than owed

defaultSelf

Allow user to forfeit collateral to clear debt (emergency exit).

function defaultSelf(BToken _bToken, address _user) external

Leverage Functions

leverage

Create a leveraged position by borrowing and buying more bTokens.

function leverage(
  BToken _bToken,
  address _user,
  uint256 _collateral,
  uint256 _leverageFactor,
  uint256 _limitAmount
) external returns (
  uint256 collateralAdded_,
  uint256 debtAdded_,
  uint256 collateralIn_,
  uint256 reservesIn_
)

Parameter	Type	Description
`_bToken`	`BToken`	The bToken to leverage
`_user`	`address`	User creating position
`_collateral`	`uint256`	Initial bToken collateral
`_leverageFactor`	`uint256`	Target leverage (WAD, e.g., 2e18 = 2x)
`_limitAmount`	`uint256`	Maximum reserves to spend (slippage)

Returns:

collateralAdded_: Total collateral after leverage
debtAdded_: Debt created
collateralIn_: bTokens used as input
reservesIn_: Reserves borrowed

deleverage

Reduce leverage by selling collateral to repay debt.

function deleverage(
  BToken _bToken,
  address _user,
  uint256 _collateralToSell,
  uint256 _limitAmount
) external returns (
  uint256 collateralRedeemed_,
  uint256 debtRepaid_,
  uint256 collateralSold_,
  uint256 refund_
)

Parameter	Type	Description
`_bToken`	`BToken`	The leveraged bToken
`_user`	`address`	User deleveraging
`_collateralToSell`	`uint256`	Collateral to sell for debt repayment
`_limitAmount`	`uint256`	Minimum reserves from sale (slippage)

View Functions

getCreditAccount

Get a user's credit account state.

function getCreditAccount(BToken _bToken, address _user) 
  external view returns (State.CreditAccount memory)

Returns: CreditAccount struct:

collateral: Locked bTokens
debt: Outstanding debt

Events

event Borrow(
  BToken bToken, 
  address user, 
  uint256 borrowed, 
  uint256 fee, 
  State.CreditAccount post
);
 
event Repay(
  BToken bToken, 
  address user, 
  uint256 collateralRedeemed, 
  uint256 debtRepaid, 
  State.CreditAccount post
);
 
event Leverage(
  BToken bToken,
  address user,
  uint256 collateralAdded,
  uint256 debtAdded,
  uint256 collateralIn,
  uint256 reservesIn,
  State.CreditAccount post
);
 
event Deleverage(
  BToken bToken,
  address user,
  uint256 collateralRedeemed,
  uint256 debtRepaid,
  uint256 collateralSold,
  uint256 refund,
  State.CreditAccount post
);
 
event DefaultSelf(BToken bToken, address user);

Errors

Error	Description
`BCredit_InsufficientCollateral`	Not enough collateral for borrow
`BCredit_RepaidMoreThanDebt`	Repaying more than owed
`BCredit_Leverage_ZeroCollateral`	Leverage with no collateral
`BCredit_Leverage_BorrowAmountTooLow`	Borrow doesn't meet minimum
`BCredit_Deleverage_InvalidCollateralToSell`	Invalid deleverage amount
`BCredit_Deleverage_Undercollateralized`	Would leave position undercollateralized

Collateral Calculation

Borrowing capacity is calculated against BLV:

Max Borrow = Collateral × BLV × LTV

Where:

Collateral = bTokens locked
BLV = Current floor price
LTV = Loan-to-value ratio (up to 90%)

Usage Example

// Borrow 900 reserves against 1000 bTokens at 90% LTV
bToken.approve(address(bcredit), 1000e18);
uint256 fee = bcredit.borrow(
  bToken,
  msg.sender,
  1000e18,  // collateral
  900e18   // borrow amount
);
 
// Create 2x leverage
bcredit.leverage(
  bToken,
  msg.sender,
  1000e18,  // initial collateral
  2e18,    // 2x leverage
  1100e18   // max reserves to use
);
 
// Repay and unlock
reserve.approve(address(bcredit), 900e18);
bcredit.repay(
  bToken,
  msg.sender,
  1000e18,  // collateral to unlock
  900e18   // debt to repay
);

Borrowing Guide : How to borrow
Leverage Guide : How to use leverage
BLV Mechanics: Why loans are 0% interest

BStaking BLens (View)