While trustless interactions on Ethereum are native to the protocol, trustless interactions between the Ethereum blockchain and other blockchains are difficult to implement. Interoperability protocols heavily rely on atomic swaps, which typically come with a free option problem. For this episode we're joined by James Prestwich, CEO at Summa. Summa designs and implements cross-chain financial contracts and instruments such as swaps, options, futures, and auctions. Summa recently conducted a dutch auction spanning the Bitcoin and Ethereum blockchains: Ethereum NFTs were auctioned off trustlessly to bidders on the Bitcoin network. We also discuss Riemann, a framework for deploying transaction scripts to UTXO-based chains, as well as the advantages of the predictability of transactions in UTXO-based chains and how to bring some of those advantages to Ethereum smart contracts. Topics discussed in this episode:James background in Japanese and how he became interested in blockchainJames contributions to Bitcoin ScriptSumma's recent cross-chain auction in which Ethereum NFTs were auctioned off to participants on the bitcoin networkRiemann, a framework for deploying script based transactions to UTXO blockchainsAtomic swaps leading to free optionsAdvantages of transaction predictability in UTXO based chains Links mentioned in this episode: Summa WebsiteCross-chain Auctions via Bitcoin Double Spends (article)Statesless SPV (article)Declarative Smart Contracts (article)Introducing Reimann (article)James Prestwich on Twitter Sponsors: Azure: Deploy enterprise-ready consortium blockchain networks that scale in just a few clicks Support the show, consider donating: BTC: 1CD83r9EzFinDNWwmRW4ssgCbhsM5bxXwg (https://epicenter.tv/tipbtc)BCC: 1M4dvWxjL5N9WniNtatKtxW7RcGV73TQTd (http://epicenter.tv/tipbch)ETH: 0x8cdb49ca5103Ce06717C4daBBFD4857183f50935 (https://epicenter.tv/tipeth) This episode is also available on :Epicenter.tvYouTubeSouncloud Watch or listen, Epicenter is available wherever you get your podcasts. Epicenter is hosted by Brian Fabian Crain, Sƒbastien Couture, Meher Roy & Sunny Aggarwal.