BIP 360: Bitcoin's Preparation for the Quantum Computer Era Begins

Bitcoin Proactively Prepares for Theoretical Quantum Threat

The Bitcoin community is taking another step toward long-term security: BIP 360 has been officially accepted into the Bitcoin Improvement Proposal repository and lays the groundwork for possible quantum resistance of the network.^[2] The proposal introduces a new output type called Pay-to-Merkle-Root (P2MR), specifically designed to minimize a theoretical long-term risk from quantum computers. Importantly: this is a precautionary measure, not a response to an acute threat. The developers are thinking in decades, not months.

This forward-looking approach once again demonstrates the technical maturity of the Bitcoin ecosystem. While other projects often act reactively, Bitcoin addresses potential vulnerabilities long before they can become a practical problem.

The Facts

BIP 360 proposes a new output type called Pay-to-Merkle-Root (P2MR).^[1] At its core, it is a modified version of Taproot outputs, but with one crucial component missing: the key path. Bitcoin developer Murch described it succinctly as "essentially Taproot without the ability to spend via the key path".^[1]

The motivation behind this proposal lies in a theoretical scenario: should quantum computers one day become sufficiently powerful, they could use algorithms like Shor's Algorithm to calculate the corresponding private key from a publicly visible public key.^[1] Taproot outputs would be particularly vulnerable, as the public key is already stored in the blockchain and can potentially remain in the UTXO set for years. Developers refer to this as a "long-exposure" risk.^[1]

P2MR addresses precisely this problem by no longer storing a single public key in the output itself, but only a Merkle root—a cryptographic summary of an entire tree of possible spending conditions.^[1] Only when the coins are actually spent is the appropriate branch of this tree revealed. "Ultimately, the introduction of BIP 360 and P2MR is a first step in a larger set of quantum-resistance proposals that will be necessary to quantum-harden Bitcoin," explained co-author Hunter Beast, Bitcoin developer and Senior Protocol Engineer at MARA.^[2]

Important to understand: P2MR itself does not yet make Bitcoin quantum-secure. Rather, the proposal creates an infrastructure into which genuine post-quantum signature schemes could later be integrated.^[1] This could be done through a redefinition of so-called OP_SUCCESS codes in Tapscript—reserved placeholders in the Bitcoin script system intended for future extensions.^[1] The proposal mentions algorithms such as ML-DSA (Dilithium) and SLH-DSA (SPHINCS+) as possible candidates for future post-quantum signatures.^[2]

The authors of the proposal—Hunter Beast, Ethan Heilman, and Isabel Foxen Duke—placed particular emphasis on formulating the BIP in a way that is understandable to non-developers as well. "Given the sensitivity of the subject matter, we aimed to ensure the BIP was written in a manner that was clear and understandable to the general public," said Duke.^[2] The development team is also already working on further proposals to address particularly vulnerable coins, such as long-term inactive holdings.^[2]

The timing of the proposal is not coincidental: governments and major technology companies are increasingly investing in post-quantum cryptography. The U.S. National Security Agency's CNSA 2.0 framework calls for quantum-secure systems by 2030, while the National Institute of Standards and Technology plans to phase out elliptic curve cryptography in federal agencies in the mid-2030s.^[2]

Analysis & Assessment

The publication of BIP 360 is a remarkable example of Bitcoin's long-term thinking and its conservative approach to protocol changes. There is currently no quantum computer that could even remotely break Bitcoin's cryptography.^[1] Nevertheless, the community is already preparing today for a scenario that may only become relevant in ten, twenty, or more years—or perhaps never.

This foresight fundamentally distinguishes Bitcoin from many other crypto projects that often prioritize short-term goals. The fact that several experienced developers are investing time and resources into a proposal that does not solve an immediate problem demonstrates the seriousness with which the technical community is working on the long-term security of the network. At the same time, the transparent communication—particularly the deliberate inclusion of a Technical Communications Specialist as co-author—shows that the topic of quantum resistance should not be misused for FUD (Fear, Uncertainty, Doubt), but rather treated objectively.

For Bitcoin users and investors, BIP 360 initially means no immediate changes. The proposal is in the draft stage and would, if ever implemented, need to be activated through a soft fork—a process that requires broad approval from developers, node operators, and the economic majority in the network.^[1] However, should P2MR be activated one day, users would have the choice to use this new output type. The slightly higher transaction sizes and associated fees would be the price for increased long-term security.^[1]

Also interesting is the parallel to similar discussions in the past. Bitcoin has repeatedly proven that it can adapt to changing technological conditions—from the introduction of SegWit to Taproot. Quantum resistance is the logical continuation of this evolution. While critics often accuse Bitcoin of inflexibility, the proactive development of BIP 360 shows the opposite: a deliberate, thoughtful adaptability without haste or panic.

Conclusion

• BIP 360 is not an emergency update, but a forward-looking measure for a theoretical long-term risk from quantum computers—the Bitcoin community plans in decades, not quarters

• The proposed P2MR output type reduces the "long exposure" of public keys, but is not yet a complete quantum solution itself; rather, it creates the infrastructure for later post-quantum signature schemes

• For users, nothing changes in the short term—BIP 360 is a draft that will take years of discussion, review, and possible implementation and requires broad community approval

• The development demonstrates Bitcoin's technical maturity and distinguishes the network from reactive projects through systematic, transparent addressing of potential future risks

• The timing aligns with global trends: while governments and technology corporations are planning post-quantum cryptography for the 2030s, Bitcoin is preparing in parallel—a sign of the protocol's institutional maturity