Seoul-based blockchain firm SovereignWallet has announced that its MetaMUI mainnet has completed a transition to quantum-resistant cryptography. The hard fork was finalized on September 13 at block 35,499,408, with the announcement shared through The Block and CoinTelegraph on September 17, New York time. The project also released its technical Blue Paper, GitHub repository, and on-chain explorer to support transparency and developer review.
A Different Account Architecture
Most blockchains derive wallet addresses from cryptographic keys, meaning that changing the algorithm normally forces holders to move assets to new addresses. In contrast, MetaMUI accounts function as decentralized identifiers where keys act as credentials registered to an identity rather than defining the balance location. This design allows key replacement without moving user funds, which the project identifies as the central achievement of the transition.
How the Transition Worked
During the hard fork, the account namespace moved from did:ssid: to did:mmui: while existing users retained their positions. When a user updates the MetaMUI wallet and unlocks it as usual, the action approves registration of a quantum-resistant Falcon-512 signing key for the inherited identity. There is no new account creation, balance transfer, or user-paid conversion fee, and custodians can register keys on behalf of clients.
Founder Focuses on Network Migration
SovereignWallet founder and Chief Architect Yoon Seok-gu explained that the real challenge is not selecting a stronger algorithm but changing a live network without forcing asset movement. He described the hard fork as a mainnet demonstration of that capability. The project views the migration as a reference case for financial infrastructure that must balance security upgrades with user continuity.
Quantum Resistance Across Signing, Identity, and Consensus
Following the transition, MetaMUI applies post-quantum signatures to transaction signing, identity, and consensus layers simultaneously. The selected algorithm is Falcon-512, chosen for its small signature size and low verification cost, which makes it suitable for payment infrastructure. Falcon is currently being standardized by the United States National Institute of Standards and Technology as FN-DSA under the draft FIPS 206 process.
Performance and Known Limitations
MetaMUI reported a median finality of about 65 milliseconds and a 99th percentile of about 524 milliseconds in a single-region setup with three validators. Throughput was presented as approximately 2,950 transactions per second, although the company noted this was derived from block occupancy rather than a load test. The Blue Paper also discloses that cross-chain design has not undergone external audit and that large-scale validator performance remains unmeasured.
Dormant Wallets and Unfinished Items
MetaMUI defines this upgrade as an in-place transition path for existing users rather than an automatic migration of every account. Dormant wallets that are never reopened will keep their legacy classical keys until users activate them through an updated wallet. This limitation was disclosed alongside other unfinished items in a dedicated section of the Blue Paper.
Institutional Demo Network Planned for Late September
Later in September, MetaMUI intends to open a whitelisted demo network for institutions. Participants will be able to test stablecoin and deposit token issuance through platform management tools without writing or auditing smart contracts. The environment will also allow verification of finality under load, identity issuance, quantum-resistant key registration, and cross-chain approval procedures.
By completing this hard fork, MetaMUI offers a practical example of how live blockchain networks can transition to post-quantum security without forcing users to move assets. The combination of decentralized identity, Falcon-512 signatures, and institutional testing tools positions the project as a candidate infrastructure for tokenized banking. While limitations remain, the announcement provides a concrete benchmark for quantum-resistant migration in operating mainnets.