Decibel Trade has turned on Aptos' Encrypted Mempool, enabling traders on the onchain exchange to hide the details of their orders while those transactions are still pending. The feature went live on October 21, 2026.
How the Encrypted Mempool works
A mempool is a public waiting area where transactions sit before validators bundle them into a block. Anyone watching can see who is in line and what they plan to do. That visibility allows bots to scan for large buys and place their own trades before and after, a practice known as frontrunning and sandwich attacks, which results in worse prices for the targeted trader.
With the new feature, users encrypt their order payloads on their own device, client-side, before the order travels to the blockchain. Not everything is hidden: the sender address and gas fee remain visible. What disappears from view is the substance of the trade—the function being called and the inputs fed into it. Validators cannot read those specifics until the trade is finalized.
The Aptos plumbing behind it
The capability became possible after Aptos activated governance proposal AIP-144, which was approved around October 12, 2026. AIP-144 introduced batch threshold encryption to the network. Decryption keys are split across the validator set, so no single party can unlock pending orders early. The design requires no additional trust assumptions beyond the validators Aptos already relies on.
Many existing anti-MEV setups lean on a trusted third party, such as a private relay, to keep orders hidden. Aptos instead builds the protection into its consensus layer. The system requires no extra hardware or outside trust mechanisms for encryption and decryption, and it keeps onchain verifiability intact.
Encryption usually comes with a speed penalty. Tests indicate this one adds roughly 20–27 ms of latency, about 14% overhead on transaction times. In tests, the system also handled over 1,000 transactions per second with low overhead.
Decibel's numbers so far
Decibel Trade is an onchain perpetuals and spot exchange incubated by Aptos Labs. It launched on mainnet in February 2026. Since then it has processed over $8.2 billion in cumulative trading volume as of mid-October 2026. About $1.3 billion of that came in the previous 30 days alone.
The exchange runs on smart contracts written in Move, Aptos' programming language. That setup lets it operate as a fully onchain central limit order book. Its markets span crypto and commodities.
What this means for traders and Aptos
For active traders, the immediate pitch is protection. Hiding order details until finalization could cut the losses that come from being sandwiched, especially on larger orders that bots love to target.
A 14% overhead is modest on paper. Whether it stays modest during volatile market spikes, when everyone is racing to get orders in at once, is the real test to watch.
The sender address and gas fee remain public, so sophisticated observers may still try to infer intent from patterns. And any new cryptographic system carries implementation risk until it has been battle-tested across many market conditions.
Key metrics to track from here include Decibel's monthly volume relative to its recent $1.3 billion run rate, how latency behaves under heavier load, and whether other Aptos-based apps adopt the Encrypted Mempool.
