Zcash is about to activate its much-anticipated network upgrade called Ironwood, also known as NU6.3, scheduled for July 28, 2026. The update will trigger at block 3,428,143 on the mainnet, expected around 4 PM Turkish time.
This rollout introduces a new hidden transaction pool and a revamped transaction format, improving privacy features and security. The new pool adapts components from the existing Orchard system and Halo2 protocols but operates with its own unique structures like a dedicated note-commit tree and nullifier set. These enhancements aim to strengthen transaction confidentiality and traceability on the Zcash blockchain.
One standout feature of Ironwood is confidential notes designed to remain secure even against future quantum computing threats. Another critical addition is the “turnstile” mechanism that boosts oversight on the total supply of ZEC tokens. This comes after significant criticism and concern around potential vulnerabilities in the old Orchard pool, which some feared could allow counterfeit Zcash tokens to be created.
Ironwood seeks to firmly control supply consistency during fund transfers to the new pool, addressing past lapses in verifying ZEC’s circulating amount. Previously, the community worried about counterfeit tokens because the system didn’t allow for full supply verification. The update hopes to eliminate this risk and restore confidence in the network’s integrity.
The Ironwood upgrade has already undergone testing on the testnet, where it was activated at block height 4,134,000. Its mainnet launch is now imminent, marking a key step for Zcash’s future development and security.
