SIP-5 is a draft proposal from Sei Labs (@Sei_Labs) that offers each EVM account on Sei Community (@SeiNetwork) a ready-made path to quantum-safe safety, with out altering addresses, balances, or transaction historical past. The proposal was filed on July 27, 2026, and introduced a day later. No quantum pc able to breaking Sei’s cryptography exists at the moment, and that’s precisely the purpose: construct the hearth escape earlier than anybody smells smoke.
Sei confirmed the discharge on X with a brief message: “The primary proposed plan for Sei to change into quantum-secure is reside.”
Why Would a Blockchain Want Quantum Safety?
Sei, like each EVM chain, secures consumer accounts with ECDSA signatures on the secp256k1 curve. That scheme has one theoretical weak spot. As soon as an account’s public key seems on-chain, a sufficiently highly effective quantum pc operating Shor’s algorithm might work backward to the non-public key and forge transactions from that account.
No person has constructed that machine, however Sei Labs notes many consultants imagine the timeline for one is accelerating. The SIP’s authors, Maja Lie and Benjamin Marsh, argue {that a} migration carried out solely after a reputable assault turns into public can be a race between account holders and attackers. The mechanism has to exist earlier than the emergency does.
How Does SIP-5 Work?
The core thought is a registry that sits alongside the present account mannequin, designed so validators can confirm a post-quantum transaction with one handle lookup and one signature test. Nothing in regards to the EVM handle format modifications. As an alternative:
- Customers bind a post-quantum verification key to their current handle. The primary supported algorithm is ML-DSA-44, a lattice-based signature scheme standardized by NIST in FIPS 204.
- All the pieces the account already has is preserved: handle, stability, nonce, transaction historical past, token approvals, and contract relationships. No funds transfer and no chain reset occurs.
- Accounts select how one can transition. DUAL mode accepts each classical and post-quantum signatures throughout a window, whereas SOLO mode switches to post-quantum solely instantly.
- A future governance vote can set a world cutoff top, referred to as H_Q within the spec, after which classical signatures cease working network-wide. No cutoff is presently scheduled.
- After a cutoff, accounts that by no means registered a quantum-safe key can now not ship transactions, however they maintain their full state and might nonetheless obtain funds and be referred to as by contracts.
- New accounts can nonetheless be created after the cutoff by way of sponsored transactions that register and fund a post-quantum handle in a single atomic step.
An algorithm identifier is constructed into the registry, so future signature schemes could be added or retired with out redesigning the system.
What Are the Commerce-Offs?
Publish-quantum cryptography is heavy. An ML-DSA-44 public secret’s 1,312 bytes and a signature is 2,420 bytes, towards 65 bytes for a classical ECDSA signature. Which means extra bandwidth, greater gasoline prices, and decrease throughput if massive numbers of accounts change over. The draft additionally caps what number of post-quantum authentication bytes can go right into a single block, so the heavier signatures can not crowd out bizarre transactions.
Sei Labs is upfront about this. SIP-5 is positioned as an emergency possibility somewhat than the tip state, and the crew says it’s researching higher-performance post-quantum schemes that might ultimately exchange it. The draft additionally flags its personal limits: it covers EVM account authorization solely, whereas consensus keys and bridge or contract-level authentication would want separate migration plans.
One element price realizing for long-term holders: the spec consists of no restoration path for accounts that miss a future cutoff, and governance can not re-enable classical signatures as soon as a cutoff takes impact. Nonetheless, migration home windows, discover durations, and pockets help are all required steps earlier than that stage might ever change into related.
What Occurs Subsequent?
SIP-5 sits in Draft standing as a Normal (Core) proposal, reviewed by Philip Su and open for group dialogue on GitHub. The rollout, if authorized, is available in levels: registration help first, then a migration window with pockets and explorer tooling, and solely after audits and monitoring an elective cutoff resolution by governance.
Sei Labs co-founder Jayendra Jog (@jayendra_jog) framed the proposal on X as insurance coverage somewhat than alarm, writing that “each account on @SeiNetwork has a path to change into quantum-secure” if a risk seems, whereas the crew works in parallel on quicker signature schemes.
SIP-5 solutions what Sei will do if quantum computing arrives forward of schedule. Whether or not accounts ever want to make use of it, and whether or not a lighter scheme replaces ML-DSA-44 earlier than they do, now sits with the group assessment that opened this week.
Sources:
- Sei Labs Weblog Official announcement submit explaining SIP-5 in plain language.
- Sei Protocol GitHub Full SIP-5 draft with the technical specification and safety concerns.
- Sei Analysis Simplified explainer of the proposal.
- Sei Community on X Announcement submit confirming the proposal is reside for assessment.
