First quantum-resistant Bitcoin transaction successfully executed, StarkWare says

Quick Take
- StarkWare announced that it has successfully demonstrated the first quantum-resistant Bitcoin transaction.
- Still, StarkWare said Bitcoin needs a protocol-level upgrade to make it fully safe from quantum computing threats.
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StarkWare announced today that it has completed the first quantum-resistant Bitcoin transaction.
This development counters the idea that a network fork is the only way to secure bitcoin holdings against quantum computing risks, the company said.
Avihu Levy, the head of StarkWare's applications division, has devised a method that adds an "extra lock" to protect holdings by using signature grinding to prevent use of public key data while transactions sit in the Bitcoin mempool.
A Bitcoin transaction is exposed to quantum attacks when it waits in the mempool before it is confirmed. During this brief window, it reveals the mathematical material that could give a future quantum computer an opportunity to forge a signature and steal the funds.
StarkWare says signature grinding closes that window by refusing to accept the first valid signature and instead brute-forcing millions of candidates until one has a shape that does not expose the public key material to quantum computers.
This method is deliberately expensive, and can take hours of computing to produce a single transaction, StarkWare added.
"There is a catch for now. Bitcoin's network only passes along transactions written in the standard formats it recognizes, and this one is unusual enough that ordinary nodes would simply ignore it," the company said. "So instead of going into the public queue, it had to be handed straight to a miner willing to accept it."
StarkWare added that MARA mined its transaction through the Slipstream service.
Lifeboats
Despite his discovery, Levy favors making Bitcoin quantum-safe through a protocol-level upgrade. This view is shared by StarkWare CEO Eli Ben-Sasson, who said Levy's method can assist the network until it implements a permanent fork.
"Avihu's breakthrough is important because it gives the psychological reassurance which we need and which the asset itself needs," Ben-Sasson said. "The important thing is that opportunities are seized. I've said before that crypto is behaving like passengers on the Titanic. What Avihu has illustrated is that there are lifeboats. That is not a reason to relax. It is a reason to build more of them, and to build them now."
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Facts Only

* StarkWare completed the first quantum-resistant Bitcoin transaction.
* Avihu Levy devised a method involving signature grinding to add an "extra lock" to holdings.
* Signature grinding prevents the exposure of public key data while transactions are in the mempool.
* Quantum attacks pose a risk when Bitcoin transactions wait in the mempool before confirmation.
* The method involves refusing the first valid signature and brute-forcing candidates for a signature that does not expose public key material to quantum computers.
* Producing a single transaction with this method can take hours of computing time.
* The method requires specialized handling, as standard nodes would ignore transactions in this format.
* MARA mined its transaction through the Slipstream service.
* StarkWare favors a protocol-level upgrade for full quantum safety.

Executive Summary

StarkWare announced the successful execution of the first quantum-resistant Bitcoin transaction. This development followed a method devised by Avihu Levy, who introduced a technique using signature grinding to protect holdings. The method aims to prevent public key data from being exposed while transactions reside in the Bitcoin mempool, as these transactions are vulnerable to quantum attacks. Signature grinding works by rejecting the first valid signature and brute-forcing candidates until one that does not expose the public key material is found. The process is computationally intensive, potentially taking hours for a single transaction. StarkWare's head of applications, Avihu Levy, noted that standard Bitcoin nodes would typically ignore this transaction format, requiring it to be passed directly to a miner. Despite this breakthrough, StarkWare maintains that a full quantum-safe solution requires a protocol-level upgrade rather than just this specific transaction method.

Full Take

The narrative presents a tension between incremental, specific technical solutions and necessary systemic evolution. The development of signature grinding illustrates an attempt to secure assets against future threats by manipulating the immediate transaction context—a tactical defense within an existing system. This approach offers psychological reassurance, as noted by StarkWare CEO Eli Ben-Sasson, by demonstrating that immediate opportunities can be seized while larger architectural changes are underway. The core pattern involves establishing a provisional "lifeboat" solution to manage existential risk while pursuing a permanent structural fix. The emphasis on the necessity of a protocol upgrade suggests an understanding that localized fixes do not equate to comprehensive security against paradigm shifts. The implication is that maintaining momentum through immediate action, even with incomplete solutions, holds value, but this requires sustained effort from the network infrastructure to implement the necessary foundational change.
What assumptions about the timeline for protocol adoption are being implicitly accepted by positioning the quantum-resistant transaction as a temporary measure? What mechanisms exist to ensure that these interim, resource-intensive methods do not become an unmanageable burden on the existing ecosystem while waiting for a full upgrade? Does focusing resources on demonstrated tactical solutions risk diverting attention from the slower, more comprehensive protocol development required for true long-term resilience?

Sentinel — Human

Confidence

The text reads like standard, well-sourced financial/technology reporting that blends specific technical details with broader strategic commentary.

Signals Detected

Moderate sentence length variance and specific technical terminology usage suggest human editing.

The narrative flows logically from a technical announcement to philosophical implications without excessive hedging.

Specific attribution (Avihu Levy, Eli Ben-Sasson) and detailed procedural descriptions anchor the claims.

The core claims about signature grinding and the context of quantum threats align with established discourse, although the specific execution details require external verification.

Human Indicators

The inclusion of a clearly demarcated disclaimer at the end is typical of journalistic practices.

The shift in tone between the technical explanation and the philosophical commentary feels organically driven.