Functions

Core functions

deposit

Supply a stablecoin to the protocol. The system records DLRS at 1:1.

function deposit(
    address stablecoin,
    uint256 amount
) external returns (uint256 dlrsMinted)

Parameter	Type	Description
stablecoin	address	Supported stablecoin to supply
amount	uint256	Amount to supply (6 decimals)

Returns: Amount of DLRS recorded (always equals amount)

Effects:

• Protocol transfers stablecoin from caller
• Processes queue for that stablecoin (fills waiting positions)
• Adds remainder to reserves
• Records DLRS for caller

Reverts if:

• amount is 0
• stablecoin not supported
• Transfer fails

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withdraw

Request a stablecoin from supply. Uses DLRS at 1:1.

function withdraw(
    address stablecoin,
    uint256 amount
) external returns (uint256 stablecoinReceived)

Parameter	Type	Description
stablecoin	address	Stablecoin to request
amount	uint256	Amount to request (6 decimals)

Returns: Amount of stablecoin received (always equals amount)

Reverts if:

• amount is 0
• stablecoin not supported
• Insufficient supply
• Caller has insufficient DLRS

---

Swap functions

swap

Swap one stablecoin for another, with optional queue fallback.

function swap(
    address fromStablecoin,
    address toStablecoin,
    uint256 amount,
    bool queueIfUnavailable
) external returns (uint256 received, uint256 positionId)

Parameter	Type	Description
fromStablecoin	address	Input stablecoin
toStablecoin	address	Output stablecoin
amount	uint256	Amount to swap
queueIfUnavailable	bool	If true, queue unfilled portion; if false, record DLRS

Returns:

• received: Amount filled instantly
• positionId: Queue position ID (0 if fully filled or not queued)

---

swapFromDLRS

Request a stablecoin using DLRS.

function swapFromDLRS(
    address toStablecoin,
    uint256 dlrsAmount,
    bool queueIfUnavailable
) external returns (uint256 received, uint256 positionId)

Parameter	Type	Description
toStablecoin	address	Output stablecoin
dlrsAmount	uint256	Amount of DLRS to use
queueIfUnavailable	bool	If true, queue unfilled portion

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swapExactInput

Aggregator-optimized swap. Never queues—either fully executes or reverts.

function swapExactInput(
    address fromStablecoin,
    address toStablecoin,
    uint256 amountIn,
    uint256 minAmountOut,
    address recipient,
    uint256 deadline
) external returns (uint256 amountOut)

Parameter	Type	Description
fromStablecoin	address	Input stablecoin
toStablecoin	address	Output stablecoin
amountIn	uint256	Exact input amount
minAmountOut	uint256	Minimum acceptable output (slippage protection)
recipient	address	Where to send output tokens
deadline	uint256	Unix timestamp deadline

Returns: Exact output amount (equals amountIn for 1:1)

Reverts if:

• Deadline passed
• Insufficient supply (no partial fills)
• Any validation fails

---

Queue functions

joinQueue

Enter the queue for a stablecoin. Commits DLRS to the protocol.

function joinQueue(
    address stablecoin,
    uint256 dlrsAmount
) external returns (uint256 positionId)

Parameter	Type	Description
stablecoin	address	Stablecoin to wait for
dlrsAmount	uint256	Amount of DLRS to commit

Returns: Unique position ID

Reverts if:

• Queue is full (150 positions max)
• Below minimum order size
• Insufficient DLRS balance

---

cancelQueue

Cancel a queue position. Protocol returns DLRS.

function cancelQueue(
    uint256 positionId
) external returns (uint256 dlrsReturned)

Returns: DLRS returned (may be less than original if partially filled)

Reverts if:

• Position doesn't exist
• Caller doesn't own position

---

View functions

getSwapQuote

Get expected output for a swap. Used by aggregators to check fillability.

function getSwapQuote(
    address fromStablecoin,
    address toStablecoin,
    uint256 amountIn
) external view returns (uint256 amountOut)

Returns: amountIn if fully fillable, 0 if not. Never returns partial amounts.

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getReserves

Get all reserve balances.

function getReserves() external view returns (
    address[] memory stablecoins,
    uint256[] memory amounts
)

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getReserve

Get reserve for a specific stablecoin.

function getReserve(address stablecoin) external view returns (uint256)

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getQueueDepth

Get total DLRS waiting in a queue.

function getQueueDepth(address stablecoin) external view returns (uint256)

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getQueuePositionCount

Get number of positions in a queue.

function getQueuePositionCount(address stablecoin) external view returns (uint256)

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getQueuePosition

Get details of a queue position.

function getQueuePosition(uint256 positionId) external view returns (
    address owner,
    address stablecoin,
    uint256 amount,
    uint256 timestamp
)

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getUserQueuePositions

Get all position IDs for a user.

function getUserQueuePositions(address user) external view returns (uint256[] memory)

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getMinimumOrderSize

Get minimum order size for a queue based on current depth.

function getMinimumOrderSize(address stablecoin) external view returns (uint256)

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supportedStablecoins

Get all supported stablecoin addresses.

function supportedStablecoins() external view returns (address[] memory)

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isSupported

Check if a stablecoin is supported.

function isSupported(address stablecoin) external view returns (bool)

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dlrsToken

Get the DLRS contract address.

function dlrsToken() external view returns (address)