Researchers at East Texas A&M University's RELLIS Campus have published PQLN — short for Post-Quantum Lightning Network — one of the first concrete, working attempts to harden Bitcoin's Lightning Network against a future quantum-computing threat. The team released the project on September 12, 2026, adding nearly 11,000 lines of new code to a fork of the popular rust-lightning implementation.
Unlike proposals that would require changing Bitcoin's base-layer consensus rules, PQLN operates as an additional cryptographic layer that runs alongside existing Lightning nodes. It layers lattice-based post-quantum algorithms — ML-DSA (a digital signature scheme) and ML-KEM (a key-encapsulation mechanism), both standardized by NIST — on top of Bitcoin's existing secp256k1 elliptic-curve cryptography, rather than replacing it outright.
Why Lightning, and Why Now
The Lightning Network handles millions of off-chain Bitcoin payments daily, relying on cryptographic commitments and signatures to secure channels between participants. While large-scale quantum computers capable of breaking secp256k1 do not yet exist, researchers argue that payment infrastructure with long-lived channels and multi-year time horizons is precisely the kind of system that should be hardened early, before the threat becomes practical rather than theoretical.
According to the team, PQLN's cryptographic operations run in under a third of a millisecond each, suggesting the added security layer would impose minimal latency on real-world Lightning payments.
How It Fits Alongside Other Quantum-Readiness Efforts
PQLN arrives amid a broader, still-early push within the Bitcoin developer community to get ahead of quantum risk. On the base-layer side, developers including Adam Back's Blockstream Research have been advancing BIP-360, a draft proposal for a new "Pay-to-Merkle-Root" (P2MR) output type that would give Bitcoin addresses a quantum-resistant option by removing the quantum-vulnerable key-path spend used in current Taproot outputs. BIP-360 was merged into the official BIP GitHub repository earlier this year, though it remains a proposal rather than an activated network rule.
PQLN takes a narrower, more immediate approach: rather than waiting on a base-layer soft fork and network-wide coordination, it demonstrates that a widely used Layer 2 payment network can adopt post-quantum defenses today, as an opt-in overlay, without requiring miners or the broader Bitcoin Core codebase to change anything.
What's Next
The full PQLN codebase is publicly available on GitHub for node operators, wallet developers, and researchers to review and test. As with most early cryptographic research of this kind, wider adoption will likely depend on independent security review, performance testing across diverse node hardware, and eventual buy-in from major Lightning implementations such as LND, Core Lightning, and Eclair. For now, PQLN stands as a proof of concept that Bitcoin's payment rails can begin preparing for a post-quantum world well ahead of any confirmed quantum threat.
28 September 2026
Country:
Global
Topic:
Scaling | Cryptography