“Layer 2s [companion systems] have single instance sequencers that act as block producers,” said Chiu. “So we set off to modify Geth [a programming language for running Ethereum nodes] in such a way that smart contracts on Boba can call any external API. Suddenly, you can do machine learning off-chain and have the results come back to your smart contract, atomically, meaning in the same transaction, in the same block.”