This week, Anna and James chat with Ben Jones and Mark Tyneway from Optimism, the builders of Optimistic Ethereum. The interview continues the series of L2-focused episodes we have been airing on the Zero Knowledge Podcast and comes just as Optimism gears up for launch. Anna, James, Ben and Mark discuss the inner workings of their Optimistic Rollup, diving deep into concepts like data availability, the fraud proof, the role of the sequencer and the rollup’s complex relationship with layer-one.