Glossary
Gulf Stream
Solana's mempool-less transaction-forwarding protocol — validators push pending transactions directly to the upcoming leader instead of buffering in a public mempool.
Solana validators know the leader schedule in advance: the upcoming block proposer is deterministic from the validator set and slot. Gulf Stream exploits this by routing each transaction directly to the next leader rather than holding it in a public mempool.
The result is no traditional public mempool on Solana, which materially changes the MEV landscape — block builders cannot inspect a pool of pending transactions because none exists in the Ethereum sense. Jito's Block Engine fills part of the equivalent role with a private auction.