QuFi Launches Post-Quantum Verification Platform With Bitcoin Testnet Proof of Concept

QuFi Network, a post-quantum infrastructure company, has launched a verification platform designed to protect digital assets against future quantum computing threats without requiring changes to existing blockchain settlement networks.

The platform separates verification from settlement, employing a decentralized network of nodes to validate transactions using post-quantum cryptography before they are settled on existing blockchain networks.

Alongside the platform, QuFi introduced uBTC, a proof-of-concept that applies the verification system to Bitcoin ($BTC) and is currently running on Bitcoin Testnet4. The uBTC system verifies $BTC collateral and generates cryptographic proofs that govern how value moves between settlement environments, while redemptions ultimately settle as standard Bitcoin transactions.

Three post-quantum cryptographic standards underpin the platform — ML-DSA-65, SLH-DSA and ML-KEM-1024 — used for digital signatures and secure key exchange. All three were standardized by the U.S. National Institute of Standards and Technology, which published its final post-quantum cryptography standards in August 2024 after a multi-year public selection process, giving the industry a common reference point for migrating away from classical schemes such as ECDSA that secure most blockchains today.

According to QuFi, the external verification layer is intended to avoid the added storage, bandwidth and computing demands that can arise when adopting larger post-quantum signatures directly on individual blockchains. That constraint has been a central obstacle for Bitcoin in particular: post-quantum signature schemes generally produce signatures and public keys far larger than the elliptic-curve equivalents, which would materially increase block and UTXO storage on a network where every node stores the full transaction history.

Crypto Ramps Up Quantum Defenses

The launch comes amid a series of recent efforts to prepare blockchain networks for potential quantum computing threats. Concerns include "harvest now, decrypt later" scenarios, in which adversaries record encrypted or signed data today with the aim of breaking it once sufficiently capable quantum computers exist — a particular issue for public blockchains, where signatures and addresses are permanently visible onchain.

In August, StarkWare tested a quantum-resistant Bitcoin transaction on mainnet without requiring a fork. The transaction, however, took hours of computation, cost roughly $150 to $200, and its nonstandard format required direct submission to a miner.

Jonas Nick announced the BIP SHRINCS proposal on Aug. 26. Source: Jonas Nick

That same month, banks and regulators across Europe, the Middle East and Asia joined a pilot testing post-quantum wallets and onchain transfers using ML-DSA-65 — one of the same cryptographic standards incorporated into QuFi's platform. Meanwhile, the Ethereum Foundation dropped the Poseidon hash function from its planned post-quantum architecture in favor of established alternatives such as SHA or BLAKE.

Bitcoin developers are also exploring protocol-level defenses. In August, Blockstream researchers published a Bitcoin Improvement Proposal for SHRINCS, an experimental post-quantum signature scheme designed to reduce the size and performance costs associated with quantum-resistant signatures.

The approach involves trade-offs. SHRINCS uses stateful signatures to reduce their size, which requires wallets to track previously used signing keys. The scheme remains at an early stage without a completed security proof, and its design adds complexity and potential user failure modes. QuFi's testnet-stage uBTC proof of concept likewise remains unproven at scale, and the project has not yet announced a mainnet timeline; how an external verification layer performs under production-level transaction volumes and adversarial conditions is a key question for observers tracking the sector's post-quantum migration.