Zakura Node Hits Four-Hour Sync as Zcash Preps July 28 Ironwood Upgrade

Zcash developers are sealing a shielded pool with a critical bug as the Ironwood hard fork (NU6.3) activates around July 28, 2026, at block height 3,428,143. The upgrade closes a soundness flaw in the Orchard shielded pool. A new fast-syncing node, Zakura Node, already supports the fix with a four-hour sync time.