Aptos Launches Encrypted Mempool To Hide Transactions Until Finality

Aptos has launched an encrypted mempool on its mainnet, concealing transaction functions and parameters until blocks reach finality in a move designed to reduce front-running and maximal extractable value, or MEV.

The feature, introduced through AIP-144, is optional on a transaction-by-transaction basis. When enabled, a client encrypts the transaction before submission. Block proposers can then order transactions without seeing their contents.

After finality, validators collectively decrypt and execute the pending transactions. Sender addresses and gas fees remain visible throughout the process.

Decryption requires the same stake-weight threshold used for block production. A single validator, or a group representing less than two-thirds of the network’s staked voting power, cannot decrypt pending transactions on its own.

A 50-node benchmark showed the system added about 20 milliseconds of latency per block, and the system passed a security review by ZKSecurity. Petra wallet already supports the feature, while Aptos-based perpetuals exchange Decibel plans to use the encrypted mempool to protect order privacy.