- Sui adds ML-DSA-65 and SLH-DSA-SHA2-128s, two NIST-standardized post-quantum signature schemes, to protect accounts from future quantum attacks.
- Users can derive quantum-safe keys from their existing recovery phrases and update their authorization keys without moving funds, thanks to address aliases.
- The rollout is optional and additive, with quantum-resistant vaults hitting mainnet this year and native ML-DSA-65 accounts expected on mainnet by Q1 2027.
The blockchain network Sui is taking a big step toward quantum readiness by integrating two post-quantum signature schemes approved by the U.S. National Institute of Standards and Technology (NIST). The move, announced on August 6, 2026, lets users optionally upgrade their accounts to quantum-safe keys derived from the same recovery phrase they already hold. It’s a practical approach that avoids forcing anyone to start from scratch, which is a huge deal in a space where migration friction often kills adoption.
For those who’ve been following the quantum threat chatter, this isn’t just another tech upgrade. It’s a direct response to the “harvest now, decrypt later” attack vector that keeps blockchain security researchers up at night. Since public keys on a blockchain are permanently exposed once a transaction is made, an attacker with a future quantum computer could theoretically reverse-engineer private keys from those exposed public keys. Sui’s team is betting that adding these NIST-backed algorithms now will save users from a nightmare scenario down the road.
Why Blockchains Are Especially Vulnerable
In most systems, a hacker needs a security breach before they can even start working on a key. But on a blockchain, the key is already out there, sitting in plain sight on the ledger. The moment an account makes a transaction, its public key becomes permanent public record. That’s a fundamental difference that makes blockchains uniquely exposed to quantum attacks. The famous Shor’s algorithm, which can break elliptic curve cryptography (the math behind most current blockchain accounts), doesn’t need any special access—it just needs a visible public key and enough quantum horsepower.
And that horsepower might be closer than we think. Back in March 2026, Google’s Quantum AI team estimated that a fault-tolerant machine with fewer than half a million physical qubits could crack a private key from a public key in minutes. That estimate sent ripples through the crypto world, prompting projects like Sui to accelerate their post-quantum plans. The threat isn’t hypothetical anymore; it’s a timeline.
Two Schemes, Two Different Risk Profiles
Sui isn’t putting all its eggs in one basket. Instead, it’s adopting two distinct algorithms, each tailored to different types of risk. ML-DSA-65 (FIPS 204) will serve as the native signature scheme for everyday accounts, while SLH-DSA-SHA2-128s (FIPS 205) will handle high-value assets inside Move smart contracts. The idea is that if one algorithm gets broken, the other still stands—they rely on completely different mathematics.
The choice of ML-DSA-65 at Level 3 security (rather than the cheaper Level 1) wasn’t arbitrary. It came after a July 2026 incident where an AI model reportedly halved the effective key strength of HAWK, another post-quantum candidate. That incident, which was approved in about 60 hours after two years of human expert review, served as a wake-up call. Sui decided to carry extra margin instead of opting for the most cost-effective parameters. The rest of the internet seems to be converging on the same choice: AWS KMS now offers ML-DSA signing in its hardware-backed key service, and Android 17’s Keystore generates quantum-safe signatures using ML-DSA-65 directly in secure hardware, skipping the full 44-parameter set.
SLH-DSA for High-Value Vaults
For assets that need extra protection, Sui is turning to hash-based signatures. SLH-DSA-SHA2-128s is considered the most conservative and well-understood post-quantum scheme, and by keeping it inside Move contracts rather than the protocol core, Sui maintains flexibility. If the industry later adopts a different standard, the network can adapt without a hard fork or protocol-level update. That’s a smart move given how interconnected Sui is with other networks and bridges.
Both algorithms are NIST-standardized and align with the CISA/NSA/NIST roadmap for quantum preparedness. This isn’t a fringe experiment; it’s mainstream security practice being applied to blockchain for the first time at scale.
No New Seed Phrases, No Asset Transfers
One of the most user-friendly aspects of this upgrade is that it doesn’t require new recovery phrases. Because Sui keys are derived deterministically from a seed, users can generate a quantum-resistant key from the same 32-byte seed they already use, just with a new derivation path. Wallets will back up and restore exactly as they do today—no panic, no confusion.
Existing accounts also get a smooth path forward thanks to address aliases, a feature already live on Sui. An account can update its authorization key to a post-quantum key without losing its address or moving its assets. No forced migration, no expensive transfers of entire account contents. It’s about as frictionless as a cryptographic transition can get.
The Cost: Bigger Signatures, But Not Slower Verification
Let’s be honest: post-quantum signatures are chunky. A post-quantum signature and public key are substantially larger than an Ed25519 pair, which means transactions will take up more space on the network. That’s the price the entire industry pays for quantum resistance. But Sui says verification is where it could have hurt—and it doesn’t. ML-DSA-65 verification is similar enough to Ed25519 that the per-signature network cost won’t increase. Sui’s transaction size limits and programmable transaction blocks absorb the rest, and further optimization is already in the works.
Deployment Timeline: What Happens When
The core implementation is already built and tested. Quantum-resistant vaults are slated for mainnet deployment this year, with native ML-DSA-65 accounts hitting testnet by the end of 2026. Full native account authentication on mainnet is targeted for Q1 2027. Wallet, SDK, and CLI support will arrive simultaneously. Independent audits are ongoing, and timelines remain flexible as testnet feedback rolls in.
It’s worth noting that this is an optional, additive feature. Post-quantum accounts are being rolled out through the same deployment path used for zkLogin and passkeys—nothing existing changes, and no application needs to do anything today. That’s a deliberate choice to avoid disrupting the ecosystem while still preparing for the future.
For those interested in the broader picture, Sui has published a detailed overview of how each of its primitives transitions to post-quantum cryptography, titled “Securing Sui in the Quantum Computing Era.”
All things considered, Sui’s move to integrate these NIST-approved schemes is a significant milestone for blockchain security. It shows that the industry can take quantum threats seriously without resorting to panic or forced migrations. By letting users keep their seed phrases and addresses, and by making the upgrade optional, Sui is setting a practical example that other chains might follow. The quantum clock is ticking, but with moves like this, the crypto world is at least starting to set its own alarm.