Overview
- The SIMD-0723 draft, filed November 5, 2026, proposes retiring durable nonces and requiring every transaction to include a recent blockhash while replacing delayed-signature flows with onchain programmatic signer programs.
- Durable nonces let signed transactions remain valid indefinitely and were the mechanism used to execute pre-signed transactions that drained the Drift protocol on April 1, 2026, of roughly $270–285 million after a reported six-month social‑engineering campaign.
- The proposal names candidate replacements such as Anza’s Programmatic Signer and Blueshift’s Vector and warns that failed program execution could leave a signed authorization usable, creating new failure modes custodians must manage.
- SIMD-0723 bars mainnet activation before May 5, 2027 and calls for at least a six-month migration window, but audits, reviews by Anza and Firedancer engineers, and exact activation timing remain unresolved.
- Custodians and institutions have raised practical concerns about large-scale migrations and changed cold‑storage models, and the shift would transfer technical and operational risk from protocol users to wallet operators and onchain programs.