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Flash Loans

Flash Loans view

What it shows

Flash loans are DeFi's strangest primitive: borrowing any amount with no collateral, provided the loan is repaid within the same transaction — if it isn't, the whole transaction reverts as though nothing happened. TraceFast detects flash-loan events and lists them with size, asset, protocol, and the transaction that carried them.

How to read it

Flash loans power three very different activities, and telling them apart is the point:

  • Arbitrage — borrow, trade across venues, repay, keep the spread. High frequency, moderate size, boring — and healthy for markets.
  • Liquidations and refinancing — capital-efficient position management by sophisticated actors.
  • Attacks — most DeFi exploits use a flash loan as their opening move, because it turns "attacker with $1M" into "attacker with $100M" for one transaction.

A flash loan wildly out of scale with its protocol's norm, followed by unusual pool activity, is the signature worth investigating. Open the transaction and read its trace — the call tree shows the full choreography: borrow, the moves in the middle, repay.