import FungibleToken from 0xf233dcee88fe0abe import SwapConfig from 0xb78ef7afa52ff906 import SwapInterfaces from 0xb78ef7afa52ff906 import SwapRouter from 0xa6850776a94e6551 import SwapFactory from 0xb063c16cac85dbd1 import LendingPool from 0x8334275bda13b2be import LendingInterfaces from 0x2df970b6cdee5735 import FiatToken from 0xb19436aae4d94622 import FungibleTokenMetadataViews from 0xf233dcee88fe0abe import IPierPair from 0x609e10301860b683 import PierPair from 0x609e10301860b683 import FlowSwapPair from 0xc6c77b9f5c7a378f import UsdcUsdtSwapPair from 0x9c6f94adf47904b5 import FlowToken from 0x1654653399040a61 import TeleportedTetherToken from 0xcfdd90d4a00f7b5b pub contract FLA { pub let profitReceiver: Address pub resource FLE_ARB: SwapInterfaces.FlashLoanExecutor { pub fun executeAndRepay(loanedToken: @FungibleToken.Vault, params: {String: AnyStruct}): @FungibleToken.Vault { pre { params.containsKey("profitReceiver") && ((params["profitReceiver"]! as! Address) == FLA.profitReceiver): "Unauthorized caller" params.containsKey("swapFrom"): "Missing swapFrom" params.containsKey("swapTo"): "Missing swapTo" params.containsKey("swapFromAddress"): "Missing swapFromAddress" params.containsKey("swapToAddress"): "Missing swapToAddress" } let profitReceiver: Address = params["profitReceiver"]! as! Address let swapFrom: String = params["swapFrom"]! as! String let swapTo: String = params["swapTo"]! as! String let swapFromAddress: Address = params["swapFromAddress"]! as! Address let swapToAddress: Address = params["swapToAddress"]! as! Address let amountIn = loanedToken.balance let amountOwed = amountIn * (1.0 + UFix64(SwapFactory.getFlashloanRateBps()) / 10000.0) + SwapConfig.ufix64NonZeroMin let t0 <- self.swapOnPlatform(vaultIn: <-loanedToken, dex: swapFrom, address: swapFromAddress) let t1 <- self.swapOnPlatform(vaultIn: <-t0, dex: swapTo, address: swapToAddress) assert(t1.balance >= amountOwed, message: "Not enough funds to repay the loan with balance ".concat(t1.balance.toString())) getAccount(profitReceiver).getCapability(/public/flowTokenReceiver).borrow<&{FungibleToken.Receiver}>()!.deposit(from: <- t1.withdraw(amount: t1.balance - amountOwed)) return <- t1 } priv fun swapOnPlatform(vaultIn: @FungibleToken.Vault, dex: String, address: Address): @FungibleToken.Vault { switch dex { case "i": let pair = getAccount(address).getCapability<&{SwapInterfaces.PairPublic}>(SwapConfig.PairPublicPath).borrow()! return <- pair.swap(vaultIn: <- vaultIn, exactAmountOut: nil) case "p": let mpool: &PierPair.Pool{IPierPair.IPool} = getAccount(address).getCapability<&PierPair.Pool{IPierPair.IPool}>(/public/metapierSwapPoolPublic).borrow()! let minfo = mpool.getReserves() if vaultIn.getType() == mpool.tokenAType { let forAmount = SwapConfig.getAmountOutVolatile(amountIn: vaultIn.balance, reserveIn: minfo[0], reserveOut: minfo[1], swapFeeRateBps: 30) return <- mpool.swap(fromVault: <- vaultIn, forAmount: forAmount) } else { let forAmount = SwapConfig.getAmountOutVolatile(amountIn: vaultIn.balance, reserveIn: minfo[1], reserveOut: minfo[0], swapFeeRateBps: 30) return <- mpool.swap(fromVault: <- vaultIn, forAmount: forAmount) } case "b": if vaultIn.getType() == Type<@FlowToken.Vault>() { let token0Vault <- FlowSwapPair.swapToken1ForToken2(from: <- (vaultIn as! @FlowToken.Vault)) return <- UsdcUsdtSwapPair.swapToken2ForToken1(from: <- token0Vault) } else { let token0Vault <- UsdcUsdtSwapPair.swapToken1ForToken2(from: <- (vaultIn as! @FiatToken.Vault)) return <- FlowSwapPair.swapToken2ForToken1(from: <- token0Vault) } } return <- vaultIn } } init(profitReceiver: Address) { self.profitReceiver = profitReceiver let pathStr = "fle_arb" let executorPrivatePath = PrivatePath(identifier: pathStr)! let executorStoragePath = StoragePath(identifier: pathStr)! destroy <- self.account.load<@AnyResource>(from: executorStoragePath) self.account.save(<- create FLE_ARB(), to: executorStoragePath) self.account.link<&{SwapInterfaces.FlashLoanExecutor}>(executorPrivatePath, target: executorStoragePath) } }

🎉Happy diving into the flow

Contract

🎉Happy diving into the flow