Zcash founder Zooko Wilcox stated that the proposed Ironwood upgrade will enable users to verify ZEC's circulating supply from the first block of activation without relying on developers or auditors. The statement addresses community concerns following disclosure of a recently remediated Orchard vulnerability. Privacy features in Zcash's shielded Orchard pool complicate verification of whether past soundness bugs could have been exploited without leaving public traces.
Ironwood Implements Turnstile Mechanism for Supply Verification
In a post on X and follow-up discussion on the Zcash Community Forum, Wilcox stated that Ironwood's purpose is to make the current circulating supply independently verifiable by any user running a full node. "When Zcash Ironwood activates, you will immediately, on Day 1 of Ironwood, gain trustless verification from your own full node that the actual supply of Zcash is correct," Wilcox wrote, referring to "16M ZEC now, 21M ZEC eventually."
Under the Ironwood proposal, transactions creating new outputs in the old Orchard pool would be rejected after activation. Funds would have to exit through Zcash's turnstile accounting mechanism before entering the new Ironwood pool. The turnstile tracks how much ZEC legitimately entered and exited a pool and blocks attempts to move out more than the amount that entered.
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Wilcox Separates Historical Exploitation from Current Supply Verification
Wilcox distinguished between two issues: whether counterfeit coins were ever created, and whether the current supply can be verified as sound after Ironwood. "This appears to be super confusing to almost everyone, because they are confusing two different things: No counterfeit coins were created. The current supply is sound," Wilcox wrote. "These are different things! I'm prioritizing the second one."
Wilcox specified the legitimate amount in the Orchard pool as 4.5 million ZEC. "It will snuff out any excess ZEC immediately, trustlessly, and globally," he stated. "It will snuff out any excess ZEC regardless of whether there actually is any excess ZEC. If there isn't, then all Ironwood does is give you the ability to prove to yourself that there isn't."
Wilcox stated he personally believes there is no counterfeit ZEC but emphasized that Ironwood is designed to remove the need for trust in his assessment or any other individual's judgment.
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FAQ
What does the Ironwood upgrade do for Zcash supply verification?
The Ironwood upgrade enables users to independently verify ZEC's circulating supply from the first block of activation through their own full node, according to Zooko Wilcox. The upgrade implements a turnstile mechanism that tracks ZEC movement and prevents more ZEC from exiting a pool than legitimately entered it.
Why did Zooko Wilcox propose the Ironwood upgrade?
Wilcox proposed Ironwood to address community concerns following disclosure of a recently remediated Orchard vulnerability. The upgrade is designed to make the current circulating supply verifiable without requiring users to trust developers, auditors, or assumptions about whether past exploitation occurred.
