flashloan-data-analyzer

## What it is FlashLoanArbitrage (published under the repository name flashloan-data-analyzer) is a Node.js command-line tool for crypto arbitrage using DeFi flash loans. The README describes a single local script, `goflash.js`, that runs on the user's own computer and interacts with a smart contract that is said to borrow, trade and repay within one transaction. ## How it works, as documented 1. The script is described as scanning ETH/USDC prices roughly every 60 seconds across five sources: Chainlink (used as the base oracle), Uniswap V2, SushiSwap, Curve Finance and Balancer. 2. It waits for a price difference of at least 0.9% (a configurable-looking threshold that the README presents as fixed) before acting, and otherwise keeps waiting to avoid losses. 3. When triggered, the contract is described as taking a flash loan in USDC, converting the user's ETH to USDC beforehand, buying ETH on the cheaper venue, selling on the more expensive one, repaying the loan and fees, then converting profit back to ETH. ## Flash-loan providers listed - Aave — 0.05% fee, liquidity quoted up to 10,000,000 USDC - dYdX — 0.05% fee, up to 500,000 USDC - Uniswap V3 — 0.01% fee, up to 5,000,000 USDC - Balancer — 0.02% fee, up to 1,000,000 USDC The README recommends dYdX or Uniswap V3 for lower fees and warns that larger loans mean larger fees. ## Running it Download `goflash.js` and `package.json`, place them in a folder, run `npm install`, then `node goflash.js`. Dependencies listed are `ethers` ^6.11.1, `inquirer` ^8.2.6 and `chalk` ^4.1.2. On first launch the script prompts either to create a new wallet or import an existing one by private key. In both cases the key is saved to `wallet.json` in the same folder, and a menu then offers: choose DeFi protocol, set loan amount in ETH (10 up to the protocol maximum), recreate wallet, import wallet, start arbitrage, or exit. Wallet balance and address are displayed in the menu header. ## Operational notes from the README - Gas must be paid in ETH; the README suggests a balance of at least 0.1 ETH for loans above 10 ETH. - Costs mentioned are trading fees (0.1%), slippage (0.05%), gas, and the flash-loan fee. - Troubleshooting covers module-format errors, malformed private keys, insufficient funds for gas, RPC reconnection, and missing ETH/USDC pairs on a venue. ## Caveats worth knowing - The README itself states that 0.9% spreads are rare in real markets, and that the script "shows a simulated opportunity occasionally for demonstration." That means the displayed opportunities are not necessarily executable or real. - The private key is stored in plaintext in `wallet.json`; the README advises adding that file to `.gitignore` and never sharing it. Even so, running this on a wallet holding real funds carries obvious key-custody risk. - Although the README repeatedly refers to a smart contract and shows a project tree, the listed structure contains only `goflash.js`, `package.json`, `wallet.json` and `README.md`, so the contract source is not documented as part of the repository. - No tests, configuration files, licence terms beyond "shared as-is for educational purposes", or fee-configuration instructions are described. - The repository description mentions analyzing market data with flash-loan insights, which matches the price-scanning portion of the README rather than the trading execution claims.