ZODL, working alongside Tachyon, Valar Group, the Zcash Foundation, and Shielded Labs, is proposing a new network upgrade and shielded pool called Ironwood. The new pool uses the existing Orchard protocol but backed by formal verification and additional independent audits. The total supply moved from Orchard to Ironwood will be verified by a turnstile, allowing anyone to audit Zcash’s circulating supply. For users, migration will be simple.
Ironwood is the next step in hardening the Zcash protocol. We plan to target its activation for late July 2026, following the zcashd end-of-support (block height 3,417,100). As with any network upgrade, timing depends on testing, review, and coordination across the ecosystem.
Current State
The recent Orchard soundness issue was discovered through ongoing security research, responsibly disclosed, and remediated through a coordinated network upgrade. There is no evidence that it was exploited, no evidence of impact to user funds, and no evidence of any change to the total ZEC supply. The issue did not affect the privacy of funds in any pool, and Orchard is live and operating normally.
Ironwood
The current Orchard pool will be closed to new deposits and internal transactions so that the funds in that pool can only move forward through the turnstile before entering Ironwood. Because the turnstile rejects any attempt to move out more ZEC than entered, users gain an immediate, trustless guarantee that no more than the correct amount of ZEC can be circulating, without waiting for anyone to migrate. The upgrade is paired with independent audits and formal verification of the circuit with the goal of ruling out any further soundness bugs.
The User Experience
Today, users can simply receive and send Orchard funds as usual. Following the upgrade, wallets that support Orchard will be able to prompt users to migrate funds with a single click.
The new pool will use the user’s existing Orchard receiver, so previously used addresses will continue to work.
Where ZODL is contributing
We have already begun this work on behalf of the community and ecosystem, including coordination with other core contributors. This work includes:
- Completion of work necessary for zcashd deprecation. This includes Zallet, a new command-line wallet that replaces the wallet built into zcashd. In parallel, Valar Group is building a wrapper so that current users of the zcashd wallet can keep using it until they migrate to Zallet.
- Participation in the formal verification of the new pool.
- Working with the Zcash Foundation on the rollout of zebrad to node operators still running zcashd.
- Updating the ZODL wallet and SDKs to support Ironwood.
- Coordinating across the community, including infrastructure and wallet providers, to ensure readiness.
- New tooling to support Zcash users and the ecosystem.
We will continue to share more as our work progresses.
