Stellar sets three-stage plan for quantum-safe migration

The Stellar Development Foundation announced a three-stage roadmap on Tuesday to move the Stellar network toward quantum-safe cryptography. Enterprise wallets can begin upgrades in 2026, and all accounts will be able to add quantum-safe signers by the end of 2027 without changing their existing addresses.

Stage one will add post-quantum signature verification to Stellar’s smart contract layer in 2026. That change is intended to let large custodians and enterprise wallets adopt quantum-resistant signing methods immediately while other parts of the network remain unchanged.

Stage two, scheduled for 2027, will introduce a protocol-level upgrade that allows every account to attach a quantum-safe signer while keeping the same account address and balance. The foundation says this design uses Stellar’s account model, where identity is separate from signing keys, to reduce the need for address migration.

The third stage would fully deprecate the current elliptic curve cryptography used for signing. The foundation says the timing of that final step will depend on advances in quantum hardware and on community readiness to complete the switch.

The roadmap targets two distinct risks tied to future quantum computers. One risk is forged validator signatures that could affect network consensus. The other, and the primary focus of the plan, is the potential to derive private keys from public keys and take over accounts. The foundation highlighted that Stellar’s public and permanent ledger could allow adversaries to harvest public keys now and use them later if quantum machines become powerful enough.

Stellar’s account model separates account identity from signing keys, which allows users and services to replace signing keys with quantum-resistant alternatives without changing the address or moving funds. The foundation said this separation will limit disruption for individual holders and for exchanges and custodians that manage many accounts.

An unresolved practical issue is how to handle dormant accounts whose owners cannot be reached. The foundation warned that any hard deadline that disables old signing keys could permanently lock funds in accounts with inaccessible holders. It said decisions about unreachable accounts will be made through open community discussion rather than by unilateral action.

The foundation referenced shifting technical timelines outside the network. The National Institute of Standards and Technology has updated guidance toward an earlier window for some quantum threats, and several technology organizations have set internal post-quantum readiness targets around 2029. Some researchers have proposed a potential “Q-Day” target near 2030. Developers for other major blockchains are also exploring mitigation strategies.

Market reaction to the announcement was limited. XLM, Stellar’s native token, traded near $0.196 and was down about 12% over the past week while it rose roughly 15% over the past 30 days.

The foundation said technical steps and timelines will be adjusted based on progress in quantum computing and feedback from the Stellar community. The phased approach is intended to give enterprises and individual account holders clear options to add quantum-safe signers while leaving policy choices about unreachable accounts to community deliberation.