key insights
- Supply exposure: Transparent addresses hold 70.4% of issued ZEC and therefore they are the primary focus of the Zcash quantum upgrade.
- Separate security measures: Private balance checks protect wallet queries and hash-based signatures address spending-key vulnerabilities for the Zcash quantum upgrade.
- Transition: Zakuras January target comes before Epochs end‑of‑2027 goal for a production‑ready post‑quantum cryptography in the Zcash quantum upgrade.
Zcash quantum upgrade plans aim for January 2027 to give payment protections that cover transparent addresses holding about 70% of issued ZEC. Zakura developers plan to add hash‑based signature instructions because of growing worries about quantum attacks while ZEC tries to recover from a sharp weekly decline.
Roman Akhtariev, an engineer at Zakura explained the timeline in an update. The proposal is still under development. The team has not confirmed a mainnet activation date, for the Zcash quantum upgrade. The planned changes would address transparent payments first, leaving shielded transactions dependent on separate cryptographic improvements.
Developers set January target for new signatures
Zakura plans to introduce post-quantum signature opcodes that allow Zcash to verify hash-based signatures. These instructions would provide an alternative to the elliptic-curve cryptography that currently secures transparent payments.
Here's our plan for quantum-safe, unlinkable, rotating taddrs. Possible with Zcash, today.
While others are worrying about the viability of rotating transparent addresses, we're already solving linkability.https://t.co/LE0OOKUKgA
— Zakura (@ZakuraZcash) October 8, 2026
Existing signature systems rely on mathematical problems that conventional computers cannot efficiently solve. However quantum computers that are powerful enough may weaken these protections. Expose funds that are linked to public keys that have been disclosed.
Hash-based signatures use hash functions instead of elliptic-curve mathematics. Developers are considering constructions such as Winternitz One-Time Signatures, commonly known as WOTS.
Akhtariev stated that the team expects the proposed instructions to reach Zcash in January. Nevertheless, the target does not confirm network activation, a finalized upgrade specification or a mandatory migration schedule.
Zakura is an alternative full-node implementation developed by Valar Group and Project Tachyon. Its work forms part of wider efforts to prepare cryptocurrency infrastructure for potential advances in quantum computing.
Transparent addresses hold most issued ZEC
The proposed upgrade focuses on transparent transactions, where blockchain records publicly expose addresses and transferred amounts. Unlike shielded payments, these transactions do not conceal their details from blockchain observers.
ZecStats data cited in reports placed approximately 11.96 million ZEC in the transparent pool on October 9. That represented around 70.4% of approximately 16.98 million issued coins, while about 4.95 million ZEC sat in shielded pools.
A transparent address generally stores a hash of its owner’s public key. Spending funds reveals the public key, potentially creating a future security concern if quantum computers can derive the corresponding private key.
Developers say moving remaining funds to a fresh address could limit exposure to a previously disclosed public key. But, if users share their extended public keys, or any other information, then it is not possible to ensure complete protection by address rotation.
The quantum upgrade to the Zcash network would therefore solve a significant part of the existing supply, but not all wallets and transactions.Shielded payments rely on different cryptographic components that require their own post-quantum safeguards.
Private balance checks strengthen wallet privacy
Alongside signature development, Zakura has introduced experimental technology that limits information servers receive during wallet balance checks. The system uses private information retrieval, or PIR, to conceal which database records a wallet requests.
Ordinary wallet synchronization can reveal a list of addresses to a service provider. That information may allow the provider to connect addresses belonging to one user, even when the blockchain does not publicly establish their relationship.
Zakura’s approach lets wallets examine compact activity filters locally before requesting relevant transaction records privately. The method supports balance checks, transaction history recovery and wallet restoration without sending a readable address list to the server.
An experimental implementation is available through the Private queries setting in the Vizor wallet. However, the technology does not hide transactions already recorded on the transparent blockchain. Instead, it protects the wallet’s searches from unnecessarily exposing address relationships.
The difference is important because quantum resistance and transaction privacy are in response to different risks. PIR helps to minimize the information revealed during wallet synchronization, and hash-based signatures help to enhance spending authorization.
Broader quantum risks put Zcash development under scrutiny
The proposed changes follow warnings from Ethereum researcher Justin Drake, who urged the cryptocurrency industry to prepare for a potential quantum-security emergency. His proposed “bunker mode” approach highlighted the need to protect funds before cryptographic threats become practical.
Zcash has also pursued longer-term protections through other development initiatives. Its July 2026 Ironwood upgrade introduced quantum-recoverable notes intended to support recovery under certain attack scenarios. Those measures do not make existing shielded transaction cryptography fully quantum-resistant.
Shielded Labs launched its Epoch project on October 1, 2026, with a goal of delivering production-ready post-quantum cryptography by the end of 2027. The project is part of a plan that goes beyond the changes that Zakura suggested in January.
At the time ZEC was trading close to $1,240 on October 9 after coming back from lower prices. Information from the reports showed that the immediate support was around $1,180 and the resistance was, near $1,305. The token stayed lower during the week, which means that the recent recovery had not fixed the losses that had happened before.
