Preparing a blockchain for quantum computers takes more than changing the keys in a wallet. The cryptography that coordinates validators, verifies their votes and supports access to network data also needs attention.
Tezos is opening that work to public testing with Quantumnet, an experimental network announced today. Built by developers at Nomadic Labs, Trilitech and other contributors, it lets validators and researchers run an early version of Tezos with post-quantum components.
“I'm pleased to see Tezos at the forefront of post-quantum preparedness,” said Tezos co-founder Arthur Breitman.
The launch gives developers a working environment to test a migration that could eventually reach mainnet. It does not make the live Tezos network fully quantum-resistant today.
Why Tezos Is Starting With a Testnet
Tezos is an open-source proof-of-stake blockchain designed for smart contracts and decentralized applications. Its validators, known as bakers, participate in securing the network and voting on protocol upgrades through on-chain governance.
That upgrade process is central to the Quantumnet strategy. Developers intend to experiment publicly, collect feedback and refine the software before submitting a proposed protocol amendment.
The work builds on the Ushuaia upgrade that Blockster covered in June. Activated June 30, Ushuaia introduced testnet-only support for quantum-resistant user keys behind a feature flag.
Those keys use ML-DSA-44, a parameter set within the ML-DSA digital-signature standard finalized by NIST. The standard is designed to resist attacks from large-scale quantum computers.
Quantumnet expands the scope from user signatures to other components involved in running the blockchain.
The Changes Go Beyond Wallet Security
According to the launch announcement, the work addresses several areas where Tezos currently depends on quantum-vulnerable cryptography.
One is the mechanism used in generating the protocol’s random seed. The experimental design removes the Verifiable Delay Function and uses a weighted rotation scheme intended to preserve fairness without requiring randomness for that process.
Another is how validators’ attestations—their votes about the chain—are combined. The team adopted a post-quantum proof system from the LeanEthereum project to aggregate individual signatures.
The announcement reports aggregation performance of more than 1,400 signatures per second on standard hardware.
That is a benchmark for a specific cryptographic operation, not a claim that Quantumnet processes 1,400 user transactions per second.
For the Data Availability Layer, which helps make published data accessible to network participants, the team selected a protocol called ZODA. Developers describe it as offering post-quantum security with essentially no additional communication overhead.
The announcement also points to earlier work on private, post-quantum transactions through TzEL. Timelock puzzles remain a lower-priority item for later development.
Together, these changes show why the transition requires work across the protocol. Replacing one signature scheme leaves other dependencies to examine.
Google’s 2029 Target Adds Urgency
The uncertainty surrounding quantum computing is about timing as well as capability. Developers need to prepare for machines powerful enough to threaten today’s public-key cryptography, even though the date of that threat remains uncertain.
Google has set a 2029 target for its post-quantum cryptography migration, citing progress in quantum hardware, error correction and estimates of the resources needed to break existing cryptography. It has also emphasized the need to migrate digital-signature systems before a cryptographically relevant quantum computer arrives.
That target is a migration deadline, not a prediction that blockchains will be broken in 2029. Its relevance is the preparation time involved: testing new algorithms, updating software and coordinating the people who operate it.
Stronger Cryptography Still Has to Run Efficiently
The practical question is what these replacements cost to operate.
The launch announcement warns that Quantumnet may require more powerful hardware than Tezos mainnet. That matters for validators: if a future upgrade substantially raises operating costs, smaller participants could find it harder to keep running nodes.
Developers therefore need to evaluate performance across the complete network. A fast signature-aggregation benchmark does not establish the overall demands on processing, memory, bandwidth or storage.
“We are doing this work early so that we have the time to learn, iterate and ultimately make sure Tezos is ready for a post-quantum future, with as smooth a transition path as possible,” said Zaynah Dargaye, Core Layer 1 Engineering Manager at Nomadic Labs.
There is also the transition itself. Wallets, applications and validator software would need a workable path to whatever changes eventually reach production. The announcement does not provide a mainnet activation date or a complete migration plan for existing users.
What Comes Next
Quantumnet is publicly available for bakers and researchers to run, with participation details provided through the Tezos Agora announcement. It is experimental software and is not intended for production use.
The next milestones are operational: testing the cryptographic replacements together, measuring their hardware requirements and resolving the remaining migration questions before seeking approval for a protocol amendment.
For Tezos, the useful result will be evidence that post-quantum protections can work under the demands of a live blockchain—and that the network can adopt them without making participation prohibitively expensive.