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Providing Liquidity

Adding Liquidity

To safely add liquidity to a pool, we recommend using the router. Adding liquidity function requires commitment to a belief about the current price, which is encoded in the amount*Desired parameters. While it is fairly safe to assume that the current fair market price is around what the current reserve ratio is for a pair due to arbitrage, it is dangerous to obtain this ratio within the same transaction as it can be easily manipulated.
In addition, the amount*Min and vReserveRatioBounds parameters should be utilized as a sanity buffer as the market price may shift drastically before the transaction is confirmed.
// Note: assume that usdc and usdt token approvals have been given to router
// and that transferFrom has been called to transfer tokens to contract from user
// the vReserveRatioBounds below is set to the absolute minimum and maximum values as an example
// it is recommended to read the virtual reserve ratio and set the appropriate values from that
vReserveRatioBounds = new uint256[2];
(vReserveRatioBounds[0], vReserveRatioBounds[1]) = (0, -1);
buniCornRouter.addLiquidity(
usdc,
usdt,
usdc-usdt-pool, // usdc-usdt pool address
1000 * 1e18, // 1000 usdc
1000 * 1e18, // 1000 usdt
999 * 1e18, // 0.1% slippage tolerance (999 usdc / 1000 usdt)
999 * 1e18, // 0.13% slippage tolerance (1000 usdc / 999 usdt)
vReserveRatioBounds
);

Removing Liquidity

As is the case with Uniswap LP tokens, Bunicorn Stable LP tokens implement meta-approvals to vastly help improve UX and save on gas costs. Hence, we recommend the usage of the removeLiquidity*withPermit* functions.
buniCornRouter.removeLiquidityWithPermit(
usdc,
usdt,
usdc-usdt-pool, // usdc-usdt pool address
100 * 1e18, // 100 usdc-usdt LP tokens
100 * 1e18, // Min receivable of 100 usdc
100 * 1e18, // Min receivable of 100 usdt
msg.sender, // send assets to msg.sender
block.timestamp, // deadline
approveMax, // boolean flag if max token allowance approval
v, // approve permit signature field
r, // approve permit signature field
s // approve permit signature field
);