Zcash prepares for a significant network evolution with the Ironwood upgrade, scheduled to activate at block 3,428,143 around 13:00 UTC on July 28. This update fundamentally alters how shielded ZEC moves, impacting nodes, wallets, and holders alike.
Transition from Orchard to Ironwood Shielded Pools
The long-standing Orchard shielded pool will no longer accept new deposits or outputs once Ironwood launches. Instead, a fresh shielded pool designed for enhanced privacy and security will take its place. This shift means anyone using Orchard addresses for receiving funds should stop immediately and update their wallets to support the new Ironwood pool to avoid transaction issues.
Introducing the Turnstile Bridge for Supply Control
One of the standout features of Ironwood is the introduction of a guarded bridge called the turnstile. It controls the flow of value exiting the Orchard pool and entering the new shielded pool. This mechanism ensures tighter supply accounting, preventing unchecked transfers that could compromise the network’s integrity. The turnstile addresses vulnerabilities discovered in previous implementations and provides a more solid way to track shielded ZEC across pools.
Node Software and Activation Considerations
The legacy zcashd client ceased support on July 18 at block 3,417,100 and will not restart ahead of the upgrade. Node operators must switch to Zebra 6.0.0 or newer to remain compatible. This change caught some smaller OTC desks off guard, highlighting the importance of preparing well in advance. Retail users and custodians are advised to treat the activation like a system change window: plan staged migrations, test with small transactions, and update software promptly to avoid disruptions.
Testnet activation on July 4 at block 4,134,000 gave developers a rehearsal for the transition, revealing subtle wallet indexing issues that were addressed ahead of mainnet. This dry run proved key for larger custody providers who spun up parallel Zebra nodes well before the mainnet switch.
The Ironwood upgrade reflects a broader trend toward sophisticated privacy features in Zcash’s ecosystem. Those interested in privacy-focused improvements might also look into the enhanced privacy pool details to better understand the technical innovations involved.
