Aptos adds opt-in encrypted transactions to mainnet

Aptos users can now encrypt transaction details before sending them, making it harder for bots to read pending trades and act on them; the network announced its Encrypted Mempool went live on mainnet on Oct. 12 in its mainnet launch announcement.

For traders, the protection is optional and comes with a higher minimum gas price, so the choice is whether hiding the trade details is worth the extra cost.

What does the feature hide, and when?

When a user opts in, a compatible wallet or app encrypts the transaction payload on the user’s device before submission. That payload includes the function being called and its arguments, such as the assets and amounts involved; the sender address and gas-fee fields remain visible. Aptos says validators order the encrypted transactions without seeing their contents, then collectively decrypt them after the block is finalized so they can execute.

The design targets frontrunning and sandwich attacks, in which bots use pending trade information to place transactions around a user’s order. Aptos says no single validator can decrypt a pending transaction, and decryption requires a two-thirds honest-stake threshold. The feature is integrated into Aptos consensus, using the same validator set that orders transactions.

What does using it cost, and what do users need?

Encrypted transactions have a minimum gas price twice the network’s base minimum, according to Cointelegraph’s report, which cites Aptos developer documentation. Aptos also reports about 20 milliseconds of added latency per block in benchmarks with 50 nodes. That is a benchmark result, not a quoted fee in dollars; the actual cost depends on the network’s base minimum and the transaction.

Users need a wallet or app that supports the feature. Aptos says Petra is the first wallet to offer an encryption option in its signing flow, while developers can use Aptos TypeScript SDK v7.0.0 or later to fetch the current epoch key and encrypt payloads. The network says existing Move contracts need no changes.

Encryption is opt-in for each transaction, so users must choose it when submitting a trade. It hides the payload only until ordering is final: transaction data is then decrypted, executed and recorded on-chain. The sender and fee remain public, and the feature does not conceal the transaction permanently.

Source material

• mainnet launch announcement — aptosnetwork.com
• Cointelegraph’s report — cointelegraph.com