How Zcash Plans to Hide Your Keys From AI and Quantum Attacks

While much of crypto is still debating “bunker mode,” one team of Zcash developers says it already has a plan.

Zakura, which builds a Zcash full node, said its team expects post-quantum signature opcodes to land in Zcash in January. Opcodes are low-level instructions that would let the network verify a new type of signature.

The goal, according to an engineering post by Roman Akhtariev, is “full post-quantum safe transparent pools with hash based signatures.”

Zcash supports two kinds of payments: shielded ones that hide the sender, recipient and amount, and transparent ones that are publicly visible, much as they are on Bitcoin. A transparent address contains a hash of a public key, which stays hidden until the owner spends from it and reveals the key onchain.

Zakura’s approach combines two defenses. Wallets would rotate to a fresh address after every transaction, keeping public keys out of view, and add a hash-based backup signature known as WOTS. Hash-based schemes avoid the elliptic-curve math that researchers fear AI or quantum computers could eventually crack.

Rotation creates a privacy problem, though. When a wallet asks a server to check balances across many addresses, the server can tell they belong to the same user. Zakura says it addresses that with private information retrieval, or PIR, a cryptographic technique that lets a wallet fetch records without revealing which ones it’s requesting. The feature is rolling out this week in the Vizor wallet, where users can already test it by toggling “private queries” in the settings.

“While others are worrying about the viability of rotating transparent addresses, we’re already solving linkability,” Zakura wrote on X.

That’s a nod to Ethereum Foundation researcher Justin Drake, who this week urged holders to calmly move funds to fresh addresses. The public response to Drake’s call to action, however, was not so calm.

Drake warned that AI-driven math could break the ECDSA signatures securing Bitcoin and Ethereum before quantum computers do, “in the worst case in months not years.” Ethereum co-founder Vitalik Buterin has since weighed in on the debate and said he believed it was “plausible” that AI-driven advancements in math could break encryption within the next two years.

The Zakura plan covers only Zcash’s transparent side, and the post didn’t say how or when the opcodes would be activated across the network.

The push comes as Zcash draws growing institutional interest, including another proposed U.S. ETF tied to the Winklevoss twins and Europe’s first Zcash ETP. It also follows an upgrade designed to make private payments three times faster.