Solana Proposes Deprecating Durable Nonces as Institutional Custodians Warn of DeFi Disruptions

Solana developers are weighing the deprecation of durable nonces following the formal submission of SIMD-0723 by developer grod220 in the Solana Improvement Documents repository ¹. The technical proposal seeks to eliminate durable nonces from the network, a mechanism that requires joint sign-off from core engineering teams before proceeding ¹. According to repository submission guidelines, the pull request requires approval from at least one Anza team member and at least one member of the Firedancer client team before it can be merged ¹.

At the time of writing, $SOL traded down 3.6% over the past 24 hours at $86.21 amid a broader market drawdown that saw $BTC fall to $74,568.

Institutional custodian Fireblocks stated in an architectural review that it supports replacing durable nonces due to operational fragility, network congestion amplification, and SVM runtime edge cases encountered at scale ². However, the custodian warned against replacing nonces with a Cross-Program Invocation (CPI) passthrough architecture, cautioning that forcing accounts to migrate authority to Program Derived Addresses (PDAs) poses systemic risks to institutional capital across millions of Solana addresses ². Fireblocks noted that native SOL accounts lack an authority field assignable to PDAs, requiring complete physical transfers of SOL holdings to new addresses ². Furthermore, active lockups on stake accounts prevent changing withdraw authority until lockup expiration ².

DeFi Compatibility and Transaction Envelopes

The custodian also highlighted direct operational clashes between CPI passthrough designs and existing DeFi protections, citing deployed code paths such as stack height guards in MarginFi and Kamino flashloans, CpiGuard in Token2022, and explicit CPI bans in Drift ². Fireblocks stated that introducing smart contracts into the critical signing path alters cold storage security guarantees and increases institutional audit burdens ².

Instead of CPI routing, Fireblocks endorsed the Transaction Envelope design as its preferred alternative, with the Sudo Instruction proposal as a viable second option ². The envelope model permits air-gapped cold keys to produce long-lived signed intents that can be wrapped in fresh execution envelopes without altering wallet identities or requiring immediate account migrations ².