Private Transactions

The blxr_private_tx endpoint allows users to send a single transaction that is added directly to the blocks generated by block builders. Private txs are automatically enrolled in the BackRunMe service and will pay back searchers a portion of the profit. The endpoint returns a transaction hash.

This service is available via both the Cloud API and Gateway API.

Submission Endpoint

• Method: blxr_private_tx

• Endpoint: api.blxrbdn.com (Cloud API)

• Gateway API Endpoint: 127.0.0.1:28333/ws (assumes WebSocket port 28333)

• Request type: HTTPS,WSS

Parameters

Parameter	Description
transaction	[Mandatory] Raw transaction bytes without 0x prefix.
timeout	[Optional] An integer value that represents the time, in seconds, needed to wait for a Private Transaction to be included in a block. If omitted, it defaults to 0. If timeout is not 0 and the transaction is not mined after the timeout value, it will be sent publicly. If the timeout is 0, no public transaction will be sent.
node_validation	[Optional, default: false] Transaction would be validated by a blockchain node, and Cloud-API returns an error message (e.g. "invalid sender" or "nonce too low") in case the raw transaction byte fails validation check.
priority_fee_refund	[Optional, default: false] Boolean. Set to true to join the Priority Fee Refund Program. Required to receive a refund, together with refund_recipient.
refund_recipient	[Optional] A string representing the wallet address to receive refund when priority_fee_refund flag is enabled.
backrunme_reward_address	[Optional] String – valid ETH address specifying where backrun rewards should be shared - See Backrunme program

Example

HTTPS - Cloud API

curl https://api.blxrbdn.com \
    --insecure \
    -X POST \
    -H "Content-Type: application/json" \
    -H "Authorization: <YOUR-AUTHORIZATION-HEADER>" \
    -d '{
         "id": "1", 
         "method": "blxr_private_tx", 
         "params": {
            "transaction": "f86b0184...e0b58219"
          }
        }'

wscat - Cloud API

wscat -c wss://api.blxrbdn.com/ws --header "Authorization: <YOUR-AUTHORIZATION-HEADER>" --no-check
> {
	"jsonrpc": "2.0", 
	"id": 1, 
	"method": "blxr_private_tx", 
	"params": {
		"transaction": "f86b0184...e0b58219",
		"mev_builders": {
			"bloxroute": "",
			"flashbots": "",
			"beaverbuild": "",
			"all": ""
		}
	}
}

Response

Cloud-API

{
    "jsonrpc": "2.0", 
    "id": "1", 
    "result": "ffd59870844e5...bfa54a69"        
}