TFTC: A Bitcoin Podcast
#207: Tom Trevethan
- Tom Trevethan, CTO of CommerceBlock, discusses statechains—a second-layer Bitcoin scaling and privacy solution that enables off-chain ownership transfer of fixed-size UTXOs without touching the blockchain.
- Mercury Wallet, CommerceBlock's implementation of statechains, launched on Bitcoin testnet and will include a GUI wallet within one to two months; currently available as a command-line client requiring Rust compilation.
- Statechains solve the capital lockup problem in discrete log contracts (DLCs) by allowing position ownership to transfer without on-chain transactions, enabling derivatives to be freely traded off-chain.
- A key trust tradeoff: the statechain entity must hold one key and be trusted to delete old private key shares after transfers; compromised by hardware trusted execution environments (Intel SGX) and remote attestation, but fundamentally relies on coordinator reputation.
- Privacy applications center on blinded coin swaps using zero-link protocols similar to Wasabi and Whirlpool, where users swap fixed-denomination UTXOs via a coordinator that cannot see which coins swap with which counterparties.
- Fee structure charges on deposit and withdrawal only; infinite swaps within the same session are free, limited only by timelocked backup transaction constraints (approximately 500 transfers per UTXO before mandatory on-chain settlement).