Enshrined Payment Channels: A Stateless, Post-Quantum, Confidential Rollup Design

Lightning-style networks force users to lock capital into pre-funded routes. Rollups avoid this but keep per-user state on-chain and expose every balance. We present findings from a design that combines both: channels hold balances encrypted under Regev/LWE, members co-sign state updates with hash-based signatures, and any channel pays any other channel through the rollup, so no routing or rebalancing is needed.

Three results stand out. First, an atomic signature: members sign hash(post-debit state, transfer tag) as one object, so authorizing a send and accepting the debit cannot be separated, removing a class of griefing attacks. Second, solvency over ciphertexts: ZK range proofs enforce non-negative balances that no one, including the block producer, can read. Third, machine-checked safety: authorization, no double-spend, solvency, and unilateral exit are proven in Lean. We close with in-browser proving benchmarks and WHIR-based on-chain verification.

Speakers: Leona Hioki

Track: Applied Cryptography