Zcash Mainnet Activates Ironwood NU6.3 Upgrade, Introducing New Shielded Pools

On July 28, Zcash activated the Ironwood NU6.3 network upgrade at block height 3,428,143, launching a new shielded pool to enhance network security and enable independent verification of ZEC circulating supply. Following the upgrade, the original Orchard pool has been restricted, preventing new funds from entering. Existing funds must be migrated out and then back into Ironwood via a turnstile, ensuring that protocol-level spending does not exceed verifiable income. Ironwood is based on a corrected protocol that has undergone formal verification and independent audits, aiming to prevent risks similar to previous Orchard declarative vulnerabilities. Wallets supporting Ironwood, such as Zodl 3.8.0, have provided migration paths, allowing users to move Orchard funds to the new pool without changing their addresses.