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 laptop able to breaking Sei’s cryptography exists right this 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 grow to be 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 laptop operating Shor’s algorithm might work backward to the personal 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 could 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 concept is a registry that sits alongside the prevailing account mannequin, designed so validators can confirm a post-quantum transaction with one handle lookup and one signature examine. Nothing concerning the EVM handle format adjustments. As an alternative:
- Customers bind a post-quantum verification key to their present handle. The primary supported algorithm is ML-DSA-44, a lattice-based signature scheme standardized by NIST in FIPS 204.
- All the things 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 the way to transition. DUAL mode accepts each classical and post-quantum signatures throughout a window, whereas SOLO mode switches to post-quantum solely immediately.
- A future governance vote can set a world cutoff top, known as H_Q within the spec, after which classical signatures cease working network-wide. No cutoff is at the moment scheduled.
- After a cutoff, accounts that by no means registered a quantum-safe key can now not ship transactions, however they hold their full state and may nonetheless obtain funds and be known as by contracts.
- New accounts can nonetheless be created after the cutoff by 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 may 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, in opposition to 65 bytes for a classical ECDSA signature. Which means extra bandwidth, greater fuel 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’t crowd out strange transactions.
Sei Labs is upfront about this. SIP-5 is positioned as an emergency choice moderately than the top state, and the staff says it’s researching higher-performance post-quantum schemes that might ultimately substitute 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 understanding for long-term holders: the spec consists of no restoration path for accounts that miss a future cutoff, and governance can’t re-enable classical signatures as soon as a cutoff takes impact. Nonetheless, migration home windows, discover durations, and pockets assist are all required steps earlier than that stage might ever grow to be related.
What Occurs Subsequent?
SIP-5 sits in Draft standing as a Customary (Core) proposal, reviewed by Philip Su and open for neighborhood dialogue on GitHub. The rollout, if authorised, is available in phases: registration assist first, then a migration window with pockets and explorer tooling, and solely after audits and monitoring an non-obligatory cutoff choice by governance.
Sei Labs co-founder Jayendra Jog (@jayendra_jog) framed the proposal on X as insurance coverage moderately than alarm, writing that “each account on @SeiNetwork has a path to grow to be quantum-secure” if a risk seems, whereas the staff 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 neighborhood overview 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 overview.
