Zap

Zap converts between USDG and allowlisted assets (USDC, USDT, ETH at launch) around the core. It lets suppliers deposit and withdraw in the asset they hold, and lets borrowers repay or receive loans in that asset. Routes and slippage caps come from RiskRegistry, swaps run through the shared DEX router, and every leftover balance returns to the caller. The core only ever sees USDG. Zap lets you:

Deposit any allowlisted token or ETH into the pool and receive sUSDG
Repay a book with any allowlisted token or ETH
Borrow USDG and receive it as another token or ETH
Withdraw sUSDG and receive another token or ETH

Addresses per network. Every address is also on Addresses.

Network	Address
Robinhood Chain testnet	0xCd9afa917A18717a1656025Ba9417486b6f341E1

The source code is src/periphery/Zap.sol on GitHub. The ABI is /abis/Zap.json.

Write methods

zapSupply

function zapSupply(address token, uint256 amountIn) external payable nonReentrant

Converts amountIn of token (or the ETH sent as msg.value) to USDG and deposits it into USDGPool for the caller. USDG passes through without a swap. Reverts with ZeroAddress if token is zero and no ETH was sent, ZeroAmount for a zero input, and InvalidRoute if the token is not allowlisted.

For ERC-20 input the caller must approve Zap for amountIn. Slippage is capped by the token’s registry route against the router quote.

Input parameters

Name	Type	Description
token	`address`	The input token. Pass the zero address and send ETH as `msg.value` to supply ETH. Ignored when `msg.value` is non-zero.
amountIn	`uint256`	Token amount to pull from the caller. Ignored for ETH.

zapRepay

function zapRepay(
    uint16 bookId,
    address token,
    uint256 amountIn
) external payable nonReentrant

Converts amountIn of token (or ETH) to USDG and repays the caller’s debt in bookId. Always live, like Stockline.repay. Excess USDG beyond the debt returns to the caller.

For ERC-20 input the caller must approve Zap for amountIn.

Input parameters

Name	Type	Description
bookId	`uint16`	The book to repay.
token	`address`	The input token, or the zero address with ETH as `msg.value`.
amountIn	`uint256`	Token amount to pull. Ignored for ETH.

borrowTo

function borrowTo(
    uint16 bookId,
    uint256 usdgAmount,
    address token
) external nonReentrant

Borrows usdgAmount USDG on the caller’s account, swaps it to token, and sends the output to the caller. The zero address or WETH delivers native ETH; USDG is sent as is. Follows Stockline borrow rules: LIVE, unpaused, caps, and LTV. Reverts with ZeroAmount for a zero amount.

The caller must first set Zap as operator with Stockline.setOperator, because Zap borrows on their behalf.

Uses core.borrow, so LIVE and pause gates apply. Caller must set this Zap as operator.

Input parameters

Name	Type	Description
bookId	`uint16`	The book to borrow against.
usdgAmount	`uint256`	USDG to borrow.
token	`address`	The output token. Zero address or WETH gives ETH; USDG gives USDG.

zapWithdraw

function zapWithdraw(uint256 usdgAmount, address token) external nonReentrant

Withdraws usdgAmount USDG from the caller’s sUSDG, swaps it to token, and sends the output to the caller. Subject to pool cash limits and the guardian pause through USDGPool.maxWithdraw.

The caller must approve Zap for the sUSDG shares that the withdrawal burns.

Input parameters

Name	Type	Description
usdgAmount	`uint256`	USDG to withdraw from the pool.
token	`address`	The output token. Zero address or WETH gives ETH; USDG gives USDG.

Events

ZappedSupply

event ZappedSupply(
    address indexed account,
    address indexed token,
    uint256 amountIn,
    uint256 usdgOut
)

Fires after a zapSupply, with the input and the USDG deposited.

ZappedRepay

event ZappedRepay(
    address indexed account,
    uint16 indexed bookId,
    address token,
    uint256 usdgOut
)

Fires after a zapRepay, with the USDG applied to the book.

BorrowedTo

event BorrowedTo(
    address indexed account,
    uint16 indexed bookId,
    address token,
    uint256 usdgIn,
    uint256 amountOut
)

Fires after a borrowTo, with the USDG borrowed and the tokens delivered.

ZappedWithdraw

event ZappedWithdraw(
    address indexed account,
    address indexed token,
    uint256 usdgIn,
    uint256 amountOut
)

Fires after a zapWithdraw, with the USDG withdrawn and the tokens delivered.

Errors

ZeroAddress

error ZeroAddress()

The constructor addresses were zero, or token was zero with no ETH sent.

ZeroAmount

error ZeroAmount()

The input amount was zero, or an ETH transfer to the caller failed.

InvalidRoute

error InvalidRoute()

The token is not allowlisted or its route does not connect to USDG.

Introduction

Using Stockline

Concepts

Developers

Ecosystem

Resources

Write methods

zapSupply

zapRepay

borrowTo

zapWithdraw

Events

ZappedSupply

ZappedRepay

BorrowedTo

ZappedWithdraw

Errors

ZeroAddress

ZeroAmount

InvalidRoute

​Write methods

​zapSupply

​zapRepay

​borrowTo

​zapWithdraw

​Events

​ZappedSupply

​ZappedRepay

​BorrowedTo

​ZappedWithdraw

​Errors

​ZeroAddress

​ZeroAmount

​InvalidRoute

Write methods

zapSupply

zapRepay

borrowTo

zapWithdraw

Events

ZappedSupply

ZappedRepay

BorrowedTo

ZappedWithdraw

Errors

ZeroAddress

ZeroAmount

InvalidRoute