Solana, Aptos Move to Harden Blockchains Against Future Quantum Attacks

As quantum computing shifted from distant theory to a practical risk in 2025, Solana developers say they have begun testing quantum-resistant cryptography to prepare for a future in which today’s technology may no longer hold up.

On Tuesday, the Solana Foundation said it had worked with post-quantum security firm Project Eleven to evaluate whether Solana’s cryptographic systems could hold up against future quantum computers, amid growing concern that advances in quantum computing could eventually undermine how blockchains secure transactions and validators.

“Quantum computers aren’t here yet, but Solana Foundation is preparing for the possibility,” the Solana Foundation wrote on X. “To that end, we’ve consulted with Project Eleven to assess our quantum readiness.”

Developers on blockchains, including Bitcoin, Ethereum, and Zcash, are discussing how their networks could address quantum computing risks. The Solana Foundation says its first step is deploying post-quantum digital signatures on a Solana testnet.

While traditionally focused on the quantum threat to Bitcoin, Project Eleven conducted a threat assessment and deployed a Solana testnet using post-quantum digital signatures. The testnet was used to evaluate whether quantum-resistant transactions could run at the network layer using current technology without disrupting the network.

“Our responsibility is to ensure Solana remains secure not just today, but decades into the future,” Vice President of Technology at the Solana Foundation, Matt Sorg, said in a statement.

The new work built on earlier efforts by Solana developers to reduce exposure to potential quantum risks. In January, the network introduced the Solana Winternitz Vault, an optional wallet feature that uses a hash-based signature scheme to protect individual user funds. The system generates new cryptographic keys for each transaction and requires users to opt in, rather than altering the protocol.

“The Solana ecosystem’s culture of shipping will continue with the release of a second client and state-of-the-art consensus mechanism this year,” Sorg wrote. “Efforts like Project Eleven’s reflect early, concrete steps to strengthen the network and stay at the forefront, ensuring Solana’s resiliency long-term.”

Other blockchain ecosystems were pursuing similar preparations. On Aptos, a proposal known as AIP-137 would introduce the network’s first post-quantum signature option if approved by token holders. The proposal would add support for SLH-DSA, a stateless, hash-based digital signature scheme standardized by researchers at the U.S. National Institute of Standards and Technology.

According to Aptos Labs, if approved, the proposal would not require a network-wide migration, and Ed25519, which Aptos uses for transaction authentication, would remain the default signature scheme, with SLH-DSA offered as an optional account type for users who want post-quantum protections.

The post-quantum scheme relies on SHA-256, a hash function already used across the network, limiting the need for new cryptographic assumptions. The tradeoff is efficiency: the signatures are larger and take longer to verify, which could increase network load if adoption expands.

Aptos Labs framed the proposal as a cautious, long-term preparation rather than a response to an immediate threat.

“Thoroughly researched and drafted by Aptos Labs’ own Head of Cryptography [Alin Tomescu], we believe that AIP-137 will empower the Aptos network to better respond to future developments in quantum computing–all while remaining in the driver’s seat, rather than under time pressure or technological surprise,” Aptos Labs wrote on X.

The Solana test and broader concerns about quantum computing stem from the possibility that sufficiently powerful machines could eventually allow attackers to derive private keys from public keys and forge signatures. While devs across the blockchain industry are looking at ways to prepare for a quantum future, researchers and developers continue to debate how soon that point could be reached.

“I think the risks are nil in the short term. This whole thing is decades away,” Blockstream co-founder and cryptographer Adam Back wrote on X. “It’s ridiculously early, and there are massive R&D challenges across every area of the applied physics required to even determine whether it’s possible at a useful scale. That said, it’s reasonable to be quantum-ready.”