Wallchain SDK

Simple integration to get MEV cashback.

$3

``typescript
import { SDK } '@wallchain/sdk';

const wallchain = new SDK({
provider //EIP-1193 provider
keys: {
matic: 'key',
...
/*
Api keys to Wallchain's contract.
Don't have keys? Contact our sales team.
*/
},
originator?: [] // platform addresses to recieve reward
originShare?: 0 //percent that you share with user, originShare ∈ [0, 50]
})
`

$3


`typescript
const transactionData = {
from: 'address',
to: 'address',
data: 'bytes',
value: 'uint',
}

const apiResponse = await wallchain.checkMEV(transactionData);
`

In case MEV is found response will be shaped this way:
`typescript
{
MEVFound: true,
cahsbackAmount: string, // in usd
masterInput: string
}
`
Or sad version of it:
`typescript
{
MEVFound: false
}
`

$3

Permit2 technology is being used to withdraw ERC-20 for executing the swap. No
need to ask for permit if swapping native token of the chain.
`typescript
const hasAllowance = await sdk.hasEnoughAllowance(sourceTokenAddress, ownerAddress, amount);

if (!hasAllowance) {
// returns Permit2 if chain supports, fallbacks to Wallchain contract
const spenderForAllowance = await sdk.getSpenderForAllowance();

}
`

$3


In case user swaps ERC-20 token, we'd need to ask for a permit to execute the
swap itself.
`typescript
const spender = await sdk.getSpender(); // Wallchain's address at current chain
const witness = await sdk.signPermit(tokenAddress, wallet, spender, value);
`
This function automaticaly calls the wallet and resolves with signature and
signed data.

$3

`typescript
const newTransaction = await sdk.createNewTransaction(
{
...originalTransaction,
isPermit, // true if not native token
amountIn, // amount of token to swap, equals msg.value when native token
srcTokenAddress,
dstTokenAddress
},
apiResp.masterInput // Resolved on step #1
witness, // resolved from step #4 or undefined
)


type newTransaction: {
from: string,
to: string,
data: string,
value: string,
gas: string
}
``

Now you can send it safe and secure.