How Do Private Transaction Relays Work to Hide Orders from Front-Runners?

Private transaction relays, such as those offered by Flashbots, allow a user to send a transaction directly to a specialized block builder or validator without broadcasting it to the public mempool. This bypasses the public waiting area where front-running bots typically operate.

The builder or validator includes the transaction in the block privately, ensuring its contents are not visible until it is already confirmed on the blockchain, thus eliminating the opportunity for a front-run.