Authentication

We support authentication via X-Flashbots-Signature Authentication is optional but will prioritize your bundles for inclusion during the block building process.

Our block building process involves multiple competing algorithms that find the most profitable block possible. By default, all bundles received go into our low priority queue.

Sending a valid signature header will bump your bundle into the next highest queue as long as you consistently use that header.

IMPORTANT: Sending an invalid header that does not correctly implement an EIP-191 signature will result in a 401 error and the bundle being dropped. Also, sending headers using unique public keys on each request will cause you to be dropped into the low priority queue.

Once an authenticated public key lands bundles, we further prioritize authenticated bundles based on your reputation score, which is a combination of your inclusion rate (how often your bundle increases our block value), and your average bundle value (max priority fees / coinbase tip).

During the block building process, our algorithms will prioritize selecting bundles for inclusion based on your reputation. Maintaining a high inclusion rate and sending high-value bundles will get you selected sooner during the build process.

A basic outline of the priority system is as follows:

• High Priority: Valid signature header + reputation

• Medium Priority: Valid signature header

• Low Priority: No signature header

• Dropped: Invalid header