Questions tagged [flash-loans]
The flash-loans tag has no usage guidance.
99
questions
0
votes
1
answer
9
views
I want to subscribe to flashloan events on the Aave v2 contract via websocket, how do I find the function/event?
I am trying to set up a websocket connection with ethers.js to listen for flashloan events.
I have made a connection successfully listening to Transfer events on the USDT contract - which was simple ...
- 1
0
votes
1
answer
40
views
pancakeswap v2 flash loan arbitrage real output amount is not as expected
when i monitor a profitable trade. The difference in profit calculated by my own method and the result of getAmoutsOut is not significant. Before sending the transaction, I would use the getAmoutsOut ...
0
votes
1
answer
19
views
Can a sandwich attack be designed using 1 flashloans and no outside capital? attacker tx, victim tx, attacker tx bundled with 1 flash loan?
So the question is can you bundle 3 transactions into one transaction where the first transaction borrows using a flash loan executes certain conditions, requires a middle victim transaction be ...
2
votes
1
answer
27
views
What's Wrong With My Polygon Mainnet Aave Flashloan Script? - Fail with error '27' & Fail with error 'ERC20: transfer amount exceeds balance'
I have successfully deployed and executed a flashloan on the Polygon network in testnet and have since adapted it for mainnet.
On Mainnet it compiles and gets deployed with no problem, but when I ...
- 23
1
vote
1
answer
109
views
Flashloan + flashbot
Can i use both flashloan and MEV builder in one transaction? Means borrowing from flashloan, then building my transaction in MEV builder (to prevent sandwich attack )?
If it is possible, can anyone ...
- 49
2
votes
1
answer
67
views
Finding IUniswapV2Callee in UniswapV2 clones for flashloans
In similar fashion to this question specific to PancakeSwap
For many UniswapV2 clones, I want to find the part of the code which is replicating IUniswapV2Callee interface, so that I can use it in a ...
- 21
1
vote
0
answers
51
views
How can I make a flashloan bot
How Can I make a flash loan bot which can operate on Aave, uniswap, sushiswap etc? I know a furucombo, but this is too complicated for me. My Idea is the bot will keep an eye on certain tokens & ...
- 149
1
vote
1
answer
44
views
flash loan arbitrage vs flash loan attack
What is the difference between a flash loan arbitrage and a flash loan attack? If I somehow find an opportunity to make a 1000% profit which crashes one or more token, will it be considered an attack? ...
- 149
0
votes
1
answer
15
views
I am studying flashloan attack. How flashloan attack is possible?
I am a beginner to learn cryptocurrency vulnerabilities. How flash loan attack is possible? Doesn't there some limit to getting a tremendous amount of flash loans?
- 115
0
votes
1
answer
65
views
Flash Loans on Etherscan
Is it possible to see all the transactions triggered by a single flash loan on etherscan?
Ex. could someone have called another contract from a single function that took a flash loan and this would be ...
- 1
0
votes
1
answer
55
views
Is there any significant advantage that UniswapV3 has over UniswapV2 in a Flashloan(or Flashswap) scenario?
I have been following the flash loan market for a while and I want to eventually experiment on it but i am having a hard time choosing between UniswapV2 and uniswapV3 for making my swaps. Is there any ...
0
votes
1
answer
42
views
How to fix gas issue
Contract address: 0x2138fF6dB5125F68E69152679D340c09d09eDEF0
USDC token address goerli: 0x9FD21bE27A2B059a288229361E2fA632D8D2d074
I sent USDC to the contract which I can see it when I invoke the &...
- 55
0
votes
1
answer
24
views
Stacked flash loan
Would it be possible to use a flash loan to flash loan?
Ex. I charge 10% for a flash loan. Someone asks my contract for money at 10% rate, so I go to Uniswap, get the money in a flash loan, and loan ...
0
votes
1
answer
36
views
Are flash loans on chain?
I'm trying to understand flash loans. It seems like because the to/from payment both happen within the same function, we cannot atomize each to a transaction on chain. Is this assumption incorrect?
0
votes
0
answers
60
views
Is it possible to use flashloan as liquidity provider?
I am reading about flash loans where I come over a use case of flash loan as providing liquidity to DEXs.
I am bit confused here. How we can earn profits by just providing liquidity to DEXs since we ...
3
votes
2
answers
227
views
TransferHelper: TRANSFER_FROM_FAILED
I want to swap some eth (that i receive from a flashloan) for x amount of a token. Then swap the token for some eth, pay back the flashloan and keep profit. For the flashloan i used dYdX and to swap i ...
- 83
2
votes
1
answer
95
views
Arbitrage Bot error: The called function should be payable if you send value and the value you send should be less than your current balance
I'm building a arbitrage trading bot with solidity. The bot should: see an opportunity on the market, execute a flashloan, swap the token retrieved from the loan for another token, swap that token to ...
- 83
1
vote
1
answer
24
views
Contract "DyDxPool" should be marked as abstract
i'm getting this error:
Contract "DyDxPool" should be marked as abstract
I have already seen others question like mine and they say that this error pops up because the contract that ...
- 83
1
vote
1
answer
911
views
Flash Loan Arbitrage Bot
I'm design an Arbitrage bot, and I wanted it to grab the funds from a flash loan.
How would you implement this?
- 46
2
votes
1
answer
164
views
Is it feasible to implement a Uniswap V3 contract integration that can simultaneously call flash and swap on the same pool in a single transaction?
We are considering the development of a Uniswap V3 flash liquidator smart contract. The liquidator will flash an amount of tokens (e.g., USDC) from the Uniswap V3 pool in order to liquidate a lending ...
- 4,336
1
vote
0
answers
113
views
Gas estimation errored. Error: Transaction reverted without a reason string
Im building a trading bot with solidity, uniswap, sushiswap and dydx for the flashloans, when i execute the executeTrade function i get this error:
Gas estimation errored with the following message (...
- 83
1
vote
0
answers
53
views
hardhat script giving this error when ran
Please, I need help clearing this.
root@DESKTOP-O7HMHFH:/mnt/c/pr0/projects/arbitrage/comp# npx hardhat run scripts/manipulate.js --network localhost
Beginning Swap...
Input Token: COMP
Output Token:...
- 31
1
vote
1
answer
228
views
Manipulating Uniswap V2's pair totalSupply via flash loan
Let's assume that I'm writing a UniswapV2 LP token price oracle. Would it be a bad idea to rely on the LP token totalSupply for my calculation? Would it be possible to manipulate its value through a ...
- 4,336
0
votes
1
answer
319
views
execution reverted: 27 HELP?
I have a simple flashloan solidity code :
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.10;
import {FlashLoanSimpleReceiverBase} from "@aave/core-v3/contracts/flashloan/base/...
0
votes
4
answers
190
views
Flash loan basics
hello everyone pls i've been trying to write some solidity code for flash loans , im kind of new to it , i would like to know after testing and deploying your smart contract with a test net without ...
- 11
0
votes
2
answers
311
views
Request flashloan fails: Gas estimation failed: 'execution reverted: 27'. This transaction will likely revert
I have written a simple flash loan smart contract with no custom logic and deployed it to goerli testnet. When I call the requestFlashLoan() function I get the following error.
Gas estimation failed: '...
1
vote
1
answer
533
views
Triangular Arbitrage or multiple swap arbitrage
Is it posible to develop a bot with a multiple step arbitrage? like 5 swaps and above? trying my hands on triangular arbitrage with bots on dexes, able to run a binary arbitrage. can i get a sample ...
- 31
0
votes
1
answer
63
views
How is a flashloan paid back automatically?
AAVE flash loan documentation states
You do not need to transfer the owed amount back to the Pool. The
funds will be automatically pulled at the conclusion of your
operation.
But how does the ether ...
- 135
0
votes
1
answer
177
views
Flash Loan Transaction
Please I need help here, I am new to flash loans. I want to understand flash loan transactions on ether scan , how to identify them, if the transaction make profit or not.
I am trying to implement a ...
- 31
1
vote
1
answer
77
views
AAVE FlashLoanV3 alowance return 0
I'm trying to make a simple flashloan contract and export it in to goerli testnet. Everything start ok, but when I call requestFlashLoan() it become error, like this:
FLashLoanArbitrage.sol
// SPDX-...
- 11
0
votes
1
answer
86
views
Flashloan in JavaScript
Is it possible to request for a flashloan for use exclusively in Javascript as opposed to in the smart contract back-end?
I have a use case need to perform some adhoc logic based on received ...
- 21
2
votes
3
answers
2k
views
Cannot estimate gas; transaction may fail
I wrote a smart contract, that is able to borrow a flashloan, make a few trades and pays the flashloan back after that. I tested the smart contract with hardhat on a mainnet fork and everything worked ...
- 63
0
votes
0
answers
56
views
FlashSwap within one DEX
Good day every one, my question is related to arbitrage within one dex and i will be glad to hear your opinions:
Lets' say i have 3 tokens A, B and C and three swap pairs. A->B (AB), B->C (BC) ...
- 101
2
votes
2
answers
3k
views
Hardhat deploy contract error: Error: cannot estimate gas; transaction may fail or may require manual gas limit
I want to deploy a FlashLoan smart contract using hardhat, and deploy the contract on hardhat network that fork by mainnet. But when I run the deploy script, keep showing Error: cannot estimate gas; ...
- 21
0
votes
1
answer
265
views
Fail with error '27' - Aave flashloans solidity
I have succesfully deployed the contract to the goerli testnet, via hardhat. However when I try to call the requestFlashLoan function with metamask, the transaction suggested gas fee seems unusually ...
0
votes
0
answers
231
views
transaction reverted while swap in polygon
Im trying to swap using Uniswap SDK on polygon mainnet. It approves, and execute the swap function from router, but the transaction get error inside blockchain, prolly because an wrong data from ...
- 1
0
votes
0
answers
100
views
I am getting "fail" error when calling flash loans aave on polygon network, when calling the loan pool
I am having error when calling flash loans aave on polygon network, when calling the pool the transaction fails "fail" here is my contract code and my bot script, what could it be?
I am ...
0
votes
0
answers
307
views
Flashloan with DyDx on mainnet-fork
I forked the Ethereum mainnet with the ganache-cli using this command below :
ganache-cli -f https://eth-mainnet.g.alchemy.com/v2/GsxpURWipc2UTubeBm3Mf-WdEyioVdwV -u ...
- 328
0
votes
0
answers
151
views
Explanation for payment logic in Uniswap FlashLoan example?
The code is here (see below): https://github.com/Uniswap/v2-periphery/blob/master/contracts/examples/ExampleFlashSwap.sol#L28
question1: to confirm, to transfer tokens, you have to first deposit into ...
- 113
0
votes
1
answer
76
views
Aave: What is the meaning of Refinancing a loan with a Flash Loan
I was watching an old video on AAVE and at around the 2:45 mark it talks about "refinance a loan with flash loan".
I am trying to understand what it means. I understand a Flash loan is a big ...
- 265
0
votes
0
answers
124
views
Writing a flashLoan function call in assembly
I am making a call for an Aave flashloan per the code block below and am getting a too deep in the stack error.
Would writing this function in assembly eliminate the error?
If yes, what would that ...
- 13
0
votes
0
answers
118
views
Flash Loan Implementation for EOA
Good day Devs.
I finished my solidity course not too long ago and currently looking into getting flash loans with a contract.
My question is : Is it possible to make the calling contract of the flash ...
0
votes
0
answers
120
views
Flashloan smart contract examples
Are there any complete examples of flashloan smart contracts that include a swapping arbitrage function and show how to enter the loan amount. Thanks in advance.
0
votes
1
answer
177
views
Flashloan Equalizer
I try to understand how to get a flashloan from euqlizer finance and make something with it. There is a documentation where they say I have to call the onFlashLoan(...) function to borrow the ...
- 21
2
votes
1
answer
334
views
Pancakeswap swapExactETHForTokens fails with non zero value in input
i have a problem with swapExactETHForTokens(). It seems to fail everytime I change the input value to something else than Zero.
To help you to follow the path of de DATA, I show you :
...
- 41
1
vote
1
answer
307
views
Problem running arbitrage flashloan test app in JS [closed]
I´ve created a JS script to test arbitrage flashloan with Ethereum blockchain. When I attempt to run this code sample directly under the Truffle command line and run the uniswapFactory.getPair(...
- 21
0
votes
1
answer
113
views
flashloan increase price of token in AMM
I've made a contract which basically do an arbitrage between two exchanges. What I couldn't understand it is that in AMM whenever the liquidity gets increased or decreased the price gets fluctuated. ...
- 79
0
votes
0
answers
60
views
How will flashloans recover funds if the borrower makes a loss?
I was studying flash loans recently which can be used for trading purposes. If we go through the smart contract code needed for the flash loans we need to repay the cost to the lender in 1 transaction ...
0
votes
1
answer
111
views
Transaction failing but I'm unsure why
I am attempting to create a test arbitrage bot on the Goerli testnet.
Here is my smart contract which should perform a swap from Uniswap to Sushiswap :
pragma solidity =0.6.6;
import './...
- 163
0
votes
1
answer
202
views
Uniswap V2 Flashswap. Pool doesn't exist
I'm trying to upgrade a flashloan file from my study and I don't get one moment about checking pool existence. Here is the code.
// Get the Factory Pair address for combined tokens
address ...
- 149