Curve Facet

The Curve Facet handles swapping in, adding liquidity to, and removing liquidity from Curve pools without assets leaving Beanstalk.

Call Functions

Exchange

function exchange(
    address pool,
    address registry,
    address fromToken,
    address toToken,
    uint256 amountIn,
    uint256 minAmountOut,
    LibTransfer.From fromMode,
    LibTransfer.To toMode
) external payable nonReentrant;

Swaps a token for another token in a Curve base, meta, plain or crypto pool. Slippage is tolerated on the amount out. It also verifies that the pool exists in the Curve Factory. This function does not support underlying tokens.

• The stable pair Curve Factory can be found at: 0xB9fC157394Af804a3578134A6585C0dc9cc990d4

• The non-stable Curve factory can be found at: 0x0959158b6040D32d04c301A72CBFD6b39E21c9AE

Parameter	Type	Description
pool	address	The address of the pool to exchange in. The pool must be registered in one of the Curve Factories.
registry	address	The Curve Registry to query pool data from.
fromToken	address	The token to swap from.
toToken	address	The token to swap to.
amountIn	uint256	The amount to swap from.
minAmountOut	uint256	The minimum amount to receive from the swap.
fromMode	From	Specifies what balance to receive the tokens from (see Internal Balances).
toMode	To	Specifies what balance to send the tokens to (see Internal Balances).

Exchange Underlying

function exchangeUnderlying(
    address pool,
    address fromToken,
    address toToken,
    uint256 amountIn,
    uint256 minAmountOut,
    LibTransfer.From fromMode,
    LibTransfer.To toMode
) external payable nonReentrant;

Swaps an underlying token for another underlying token in a Curve metapool. In a Curve metapool, one of the tokens is an LP token of another pool. Underlying tokens include the non-LP token in the pool as well as the tokens in the pool that the LP token belongs to. For example, in the BEAN:3CRV metapool, the underlying tokens are Bean, USDC, Tether and Dai.

Slippage is tolerated on the amount out. This function verifies that the pool exists in the Curve Factory.

Parameter	Type	Description
pool	address	The address of the pool to exchange in. The pool must be registered in one of the Curve Factories.
fromToken	address	The underlying token to swap from.
toToken	address	The underlying token to swap to.
amountIn	uint256	The amount to swap from.
minAmountOut	uint256	The minimum amount to receive from the swap.
fromMode	From	Specifies what balance to receive the tokens from (see Internal Balances).
toMode	To	Specifies what balance to send the tokens to (see Internal Balances).

Add Liquidity

function addLiquidity(
    address pool,
    address registry,
    uint256[] memory amounts,
    uint256 minAmountOut,
    LibTransfer.From fromMode,
    LibTransfer.To toMode
) external payable nonReentrant;

Adds tokens into a liquidity pool on Curve in exchange for LP tokens.

Parameter	Type	Description
pool	address	The address of the pool to exchange in. The pool must be registered in one of the Curve Factories.
registry	address	The Curve Registry to query pool data from.
amounts	uint256[]	The amount of each token to add.
minAmountOut	uint256	The minimum amount to receive from the swap.
fromMode	From	Specifies what balance to receive the tokens from (see Internal Balances).
toMode	To	Specifies what balance to send the tokens to (see Internal Balances).

Remove Liquidity

function removeLiquidity(
    address pool,
    address registry,
    uint256 amountIn,
    uint256[] calldata minAmountsOut,
    LibTransfer.From fromMode,
    LibTransfer.To toMode
) external payable nonReentrant;

Removes liquidity from a pool on Curve in exchange for equal amounts of all tokens in the liquidity pool. The Farmer burns their LP tokens in the process.

Parameter	Type	Description
pool	address	The address of the pool to exchange in. The pool must be registered in one of the Curve Factories.
registry	address	The Curve Registry to query pool data from.
amountIn	uint256	The amount of LP to remove.
minAmountsOut	uint256[]	The minimum amount to receive in each of the tokens.
fromMode	From	Specifies what balance to receive the tokens from (see Internal Balances).
toMode	To	Specifies what balance to sent the tokens to (see Internal Balances).

Remove Liquidity Imbalance

function removeLiquidityImbalance(
    address pool,
    address registry,
    uint256[] calldata amountsOut,
    uint256 maxAmountIn,
    LibTransfer.From fromMode,
    LibTransfer.To toMode
) external payable nonReentrant;

Removes liquidity from a pool on Curve in exchange for an unequal amounts of tokens in the liquidity pool. The Farmer burns LP tokens in the process.

Parameter	Type	Description
pool	address	The address of the pool to exchange in. The pool must be registered in one of the Curve Factories.
registry	address	The Curve Registry to query pool data from.
amountsOut	uint256[]	The amount of each token to receive.
maxAmountIn	uint256	The max amount of LP tokens to burn.
fromMode	From	Specifies what balance to receive the tokens from (see Internal Balances).
toMode	To	Specifies what balance to send the tokens to (see Internal Balances).

Remove Liquidity One Token

function removeLiquidityOneToken(
    address pool,
    address registry,
    address toToken,
    uint256 amountIn,
    uint256 minAmountOut,
    LibTransfer.From fromMode,
    LibTransfer.To toMode
) external payable nonReentrant;

Removes liquidity from a pool on Curve in exchange for an amount of one token in the liquidity pool. The Farmer burns LP tokens in the process.

Parameter	Type	Description
pool	address	The address of the pool to exchange in. The pool must be registered in one of the Curve Factories.
registry	address	The Curve Registry to query pool data from.
toToken	address	The token to receive in exchange for burning LP tokens.
amountIn	uint256	The amount of LP tokens to burn.
minAmountOut	uint256	The minimum amount of the token to receive.
fromMode	From	Specifies what balance to receive the tokens from (see Internal Balances).
toMode	To	Specifies what balance to send the tokens to (see Internal Balances).

View Functions

None.

Events

None.