Bid on Polygon transactions

Polygon is the only chain that works differently than Ethereum and BNB. There are no builders on Polygon, so we rely on a partner called FastLane to run the auctions.

The backrun transaction on Polygon needs to call the Fastlane auction contract at:


The backrun transaction is required to call the submitFlashBidWithRefund endpoint with:

  • at least 1 MATIC of bid amount

  • the refund address must be:

  • the oppTxHash must be the transaction target's hash

If your bid is not valid, you will receive an error from relay url explaining what the issue is. Bids must be submitted to the Merkle bundle relay with the following format:


    "method": "eth_sendBundle",
    "jsonrpc": "2.0",
    "params": [
            "txs": [
                "0x....", // the hash of the target transaction
                "0x....", // your signed backrun

Last updated