What Is Being Planned for January?

The team behind Zakura, a Zcash full node, said it plans to bring post-quantum signature opcodes to Zcash in January to protect funds held in transparent addresses. Roman Akhtariev wrote in an engineering post: “Our team plans for post-quantum signature opcodes to land in Zcash in January.” The post named no Mainnet activation date.

That means January is described as an engineering target, not a confirmed date for the live Zcash network to activate the change.

The post said full post-quantum-safe transparent pools using hash-based signatures are targeted for January. In the meantime, it said, wallets can pair a hash-based signature scheme called WOTS with the usual elliptic-curve key to get post-quantum-safe rotating transparent addresses today, though no integrated wallet flow for that exists yet.

For newcomers, that gap matters: the idea may be technically possible, but it is not yet a simple setting users can turn on across wallets.

Why Transparent Zcash Addresses Are the Focus

Transparent Zcash transactions stay public on-chain, Zakura said. A transparent Zcash address holds a hash of a public key, and spending from it publishes that key.

Once the public key is visible, any weakness in the signature scheme behind that key can become a risk to funds still associated with it.

Zakura said funds left at an address after a spend can go to a new address whose public key is still undisclosed. That adds protection if public keys can be attacked but the hashes stay secure.

The January target is therefore aimed at the part of Zcash that behaves like a public blockchain address: visible transactions, public balances, and spend-time key exposure.

How Rotating Addresses Could Reduce Risk

A rotating address model uses a new transparent address after a spend instead of repeatedly spending from the same address.

Because the new address’s public key is not published until it is used, the remaining funds may be protected behind a hash rather than a visible public key.

This approach does not make the chain private. The transactions are still visible on-chain. The protection comes from keeping the spending key hidden until the moment it is needed, while moving funds to fresh addresses when a spend has already exposed a key.

The Lookup Problem: Why Private Queries Matter

The catch is lookups.

A wallet that checks many rotating addresses through an ordinary server request tells that server the addresses share one owner, even if the chain shows no link.

In other words, the blockchain may not reveal the connection, but the wallet’s query pattern can leak that the addresses belong to one user.

Zakura’s answer is private information retrieval, or PIR, which lets a wallet fetch a record without the server learning which one.

Confirmed transparent activity is split into block ranges, each served by a shard that publishes a compact filter the wallet checks locally. The wallet makes a private lookup only when a filter signals a possible match. Zakura said a range with 10,000 distinct payment scripts needs roughly 15 KB of filter data.

The same method can rebuild a wallet’s history from a mnemonic, including addresses that now hold nothing.

A mnemonic is the recovery phrase that can recreate a wallet’s addresses, so the method may help users restore a complete set of past and future address states without asking a server to reveal the full list.

The post said the PIR component is coming to the Vizor wallet, and an experimental version can already be tested by turning on “Private queries” in settings.

PIR protects the lookups wallets use to manage transparent Zcash activity, while the transactions themselves remain public on-chain.

Why the Broader Post-Quantum Debate Matters

The Zakura plan is part of a wider crypto security conversation.

Ethereum Foundation researcher Justin Drake called on the industry on Oct. 7 to begin planning for “bunker mode,” an effort to shift funds into fresh addresses that have never signed a transaction.

He said it is reasonable to brace for ECDSA breaking before quantum computers arrive, in the worst case “in months not years,” and urged holders not to rush or panic.

ECDSA is an elliptic-curve digital signature method used to authorize transactions. The concern raised in that context is not only that quantum computers may exist, but that the transition period itself may create risk: old addresses with exposed public keys could remain vulnerable while the ecosystem moves to new protection methods.

What This Means for Users

For users, the January target signals that Zcash transparent-address security is being treated as a practical engineering problem, not only a theoretical post-quantum discussion.

The plan includes post-quantum signature opcodes and hash-based transparent pools, plus wallet-level tools such as rotating addresses and PIR queries.

The practical takeaway is to watch for integrated wallet flows and official activation details. The post named no Mainnet activation date, and the current rotating-address method has no integrated wallet flow yet.

The experimental “Private queries” option in Vizor shows progress, but it is still an early way to test private lookups rather than a finished user experience.

The original report was published by Unchained.