Aptos launches encrypted mempool to shield transaction details
Aptos has made encrypted transactions available on mainnet, hiding payloads until block finality to make it harder for validators and bots to exploit order flow.
BitCurrent Newsroom2 min read
On public blockchains, visible pending transactions can expose traders to frontrunning and sandwich attacks. Aptos says its encrypted mempool is now live on mainnet, letting users hide transaction details until a block is finalized.
- Launch announcement: October 12.
- About 20 milliseconds of added latency per block in 50-node benchmarks.
- Decryption requires a two-thirds stake-weight threshold.
According to the Aptos mainnet announcement, encryption is optional for each transaction. The sender address and gas fee remain visible.
What does the encrypted mempool hide?
It hides the transaction payload: the function being called and its arguments. The client encrypts that information before submission, so the block leader orders transactions without seeing their contents.
After consensus finalizes a block, validators collectively decrypt the included transactions and execute them. Aptos says no single validator, or group below the two-thirds honest-stake threshold, can decrypt a pending transaction alone.
The design aims to limit opportunities to trade against visible transaction intent. It does not make transactions fully private: sender addresses and fees remain exposed, and transaction data is recorded on-chain after finality.
Does using it require a new trusted party?
No additional party is introduced for decryption. Aptos says the validators that order transactions also hold the decryption shares, under the same trust assumption used for consensus.
The TokenPost report says Aptos introduced the feature through AIP-144. Petra wallet supports it, while Aptos-based perpetuals exchange Decibel plans to use it.
The latency figure comes from Aptos’s 50-node benchmark against its production AptosBFT implementation. Aptos says blocks finalize in under a second, making the measured overhead a small share of block time.
How much protection does the launch confirm?
The confirmed change is that users can submit encrypted payloads and validators decrypt them after finality. That timing is designed to make pre-execution inspection harder.
The launch announcement does not establish how much frontrunning or sandwich activity the feature will prevent in practice. Use is opt-in, and visible sender and fee data leave some transaction metadata exposed.
Source material
- Aptos mainnet announcement — aptosnetwork.com
- TokenPost report — tokenpost.com