Bitcoin tests quantum-resistant transactions as Solana cuts 18.9M SOL from future supply

Two major upgrades aim to secure Bitcoin and Solana for the future

Bitcoin developers have taken the first real-world steps toward protecting the network from future quantum computing threats, while Solana’s community voted to sharply reduce the supply of its native token, SOL. The moves address long-term risks: quantum computers that could one day break Bitcoin’s security, and Solana’s inflation rate, which critics say has held back its growth.

On Bitcoin, researchers from StarkWare and Blockstream tested and proposed new quantum-resistant signatures—a type of digital verification that even quantum computers couldn’t easily fake or break. Meanwhile, Solana’s validators approved a plan to cut 18.9 million SOL from future circulation, speeding up the timeline to reach a stable 1.5% annual inflation rate.

The changes reflect broader trends: Bitcoin preparing for theoretical future threats, and Solana adjusting its economics to compete with lower-inflation blockchains like Ethereum.

Key developments this week

• Bitcoin’s quantum experiments: StarkWare’s test transaction used a new signature scheme to protect funds during the brief window when they’re most vulnerable. Blockstream’s proposed SHRINCS upgrade would make all Bitcoin transactions quantum-safe—but at a cost of larger transaction sizes.
• Solana’s inflation cut: Validators approved a plan to double the annual disinflation rate from 15% to 30%, reducing future SOL supply by 18.9 million tokens. The target 1.5% inflation rate will now arrive in 2.8 years instead of 5.7.
• Record activity: Solana processed 4.2 billion transactions in July, up 91% since December, as demand for its blockchain grows.

How Bitcoin’s quantum defenses work

The two approaches tackle different stages of a quantum attack:

• StarkWare’s short-term fix: Researcher Avihu Levy’s Quantum Safe Bitcoin (QSB) scheme combines one-time signatures with extra computational steps to bind a transaction to a specific output. The test on Bitcoin’s main network worked but was impractical for daily use—each transaction took hours and cost $150–$200 in fees. It’s designed as a last-resort protection for the brief period when a transaction’s public key is exposed in the mempool (the waiting area for unconfirmed transactions).
• Blockstream’s long-term upgrade: The proposed SHRINCS signature scheme would replace Bitcoin’s current system with one resistant to quantum attacks. Blockstream reduced its size by 13.23×, but it’s still nine times larger than today’s signatures. Jonas Nick, a Blockstream researcher, called it “the first concrete proposal for a post-quantum signature scheme designed specifically for Bitcoin,” acknowledging trade-offs in speed and cost.

Neither solution is ready for widespread use. StarkWare’s method is too slow and expensive for regular transactions, while SHRINCS would require a network-wide upgrade—a complex process for Bitcoin. Still, the tests mark the first real progress toward quantum resistance since experts began warning about the threat years ago.

Solana’s vote to curb inflation

Solana’s validators—the operators who secure the network—voted 67% in favor of SGP-0002, also called the “Double Disinflation” proposal. The change accelerates the reduction of SOL’s inflation rate, which currently sits at around 5% annually. Key details:

• Faster timeline: The 1.5% “terminal” inflation rate will now arrive in ~2.8 years, versus ~5.7 years under the old plan.
• Supply cut: 18.9 million fewer SOL tokens will enter circulation over the next six years.
• Voter turnout: 60.7% of eligible stake participated, with 25.16% opposing the change.

The move follows a surge in Solana’s usage: the network processed a record 4.2 billion transactions in July, up 13.5% from June and 91% since December. Proponents argue lower inflation will make SOL more attractive to long-term holders, similar to Ethereum’s shift to a deflationary model after its 2022 upgrade.

Why these changes matter

For Bitcoin: Quantum computers don’t yet exist at the scale needed to break Bitcoin’s security, but researchers warn the threat could arrive within decades. The tests this week show Bitcoin’s development community is treating the risk seriously, even if practical solutions remain years away. A successful quantum attack could let an attacker steal funds or disrupt the network, so early experiments help prepare for that scenario.

For Solana: High inflation has been a persistent critique of SOL, with new tokens diluting the value of existing holdings. By cutting future supply, Solana aims to make SOL scarcer—and potentially more valuable—over time. The vote also signals that validators, who earn a portion of inflation rewards, are willing to accept shorter-term profits for long-term growth. With transaction volume hitting records, the network is betting that demand will outpace the reduced supply.

What’s next

Bitcoin: The SHRINCS proposal will undergo further review by developers and miners. Even if adopted, a network-wide upgrade would require near-universal consensus—a process that could take years. StarkWare’s quantum-resistant transaction method may see further testing as a niche tool for high-value transfers.

Solana: The disinflation schedule takes effect immediately, with the inflation rate dropping faster starting now. The next milestone is reaching the 1.5% terminal rate in late 2029. Developers will also monitor whether the change affects validator incentives or network security.

Sources

• Cointelegraph: Bitcoin’s new quantum defenses, 18.9M SOL cancelled
• Cointelegraph: StarkWare tests quantum-resistant Bitcoin transaction
• Cointelegraph: SHRINCS BIP published for quantum-secure Bitcoin
• Cointelegraph: Solana validators approve disinflation proposal