Zcash tests 25-second blocks, with faster payments and a deadline for older wallets

A Zcash service that waits for three transaction confirmations could see its target wait fall from 225 seconds to about 75 seconds. That is the practical promise of NU7, an upgrade now running on Zcash’s public test network, according to CoinDesk. But the faster pace comes with another change: people holding funds in its oldest private-payment system will need to move them before the upgrade reaches the live network.

NU7 became active at test-network block 4,465,026. A block is a batch of transactions recorded on the network, and the upgrade lowers the target interval between batches from 75 seconds to 25. Zakura, software that checks Zcash transactions and follows the network, lists the new rules as active. An earlier, separate testing network has been closed, putting the public trial at the centre of preparations for the planned November launch.

Faster blocks, not faster coin creation

For merchants and exchanges, the potential gain is a shorter wait before accepting a payment or crediting a deposit. The three-confirmation example assumes a service keeps its existing requirement for how many blocks must confirm a transaction. It is also a target, not a guarantee: actual block times vary. The trial gives wallets, exchanges and developers a way to check how their systems handle the quicker rhythm before it affects real ZEC, Zcash’s coin.

The test network uses coins with no monetary value. Both major programs used to run Zcash nodes—the computers that follow and check the network—now support the trial. Zakura released its implementation on Oct. 1, and the Zcash Foundation issued a test version of Zebra on Oct. 2. Operators must use compatible software to stay connected to the upgraded test network under its new rules.

More frequent blocks will not mean three times as many new coins. NU7 reduces the scheduled reward for each block to one-third of its previous level, keeping ZEC’s issuance schedule intact. That distinction matters because block production and coin creation are linked through the rewards paid to miners, who check transactions. The upgrade changes how often those rewards arrive without accelerating the scheduled supply of new ZEC.

A fee reserve and a migration deadline

NU7 also reshapes the handling of transaction fees. Miners receive 40%, while 60% is taken out of circulation and recorded in a reserve intended to support future mining rewards, CoinDesk reported. Those rewards compensate miners for continuing to check transactions as the amount of newly created ZEC declines. The fee change is therefore part of the same trial as the shorter block interval.

For some holders, the more immediate task concerns Sprout, Zcash’s oldest private-payment system. NU7 disables transactions using that system. Anyone with funds there needs to move them before mainnet activation—the switch on the live network—to retain the ability to spend them through the existing system. Developers plan to review the trial and make a mainnet decision on Oct. 20. Nov. 5 remains the target launch date, but no activation block has yet been set.