Mysten Labs rolled out the Sui mainnet-v1.74.1 upgrade, which allows zero-gas transaction simulation for flows eligible under Sui’s gasless tier. This change eliminates previous limitations where wallets and decentralized applications (dApps) had to use a non-zero gas price to simulate transactions, causing inaccurate previews and complicating testing workflows for stablecoin transfers and other fee-exempt operations.
Transaction simulation enables users and wallet developers to preview transaction outcomes before execution, showing whether a transfer will succeed or fail, the state changes involved, and the required gas fees without broadcasting any transaction on-chain. Before this update, Sui’s gRPC simulation endpoint rejected requests with a zero gas price, even when the actual transaction qualified for gasless execution. The new protocol adjustment now aligns the simulation function with the live network’s behavior, reducing discrepancies and lowering the risk of transaction failures after signing.
This enhancement is particularly significant for users conducting peer-to-peer stablecoin payments on Sui. Since the gasless transfer feature was introduced in v1.72.2, qualified transactions could avoid gas fees on transfers exceeding the minimum threshold. Now, wallets benefit from precise simulation of these transfers, allowing users to confirm transaction accuracy without holding SUI tokens for gas.
Besides transaction simulation improvements, the update addresses node stability with two critical fixes. One fix automatically disconnects persistently unreachable state-sync peers to stop nodes from wasting resources on failed connections. The other fix resolves an issue causing unexpected shutdown panics during node restart or termination. These maintenance measures form part of ongoing efforts to strengthen network reliability following multiple outages in late May.
The release corresponds to protocol version 128 and continues Sui’s hardening cycle. Such protocol upgrades ensure the blockchain’s underlying infrastructure stays robust while enhancing user experience through more reliable and accurate transaction handling.