Before I left Expo, I built a version of Expo Go that had dynamically vendored built-ins so you could do: import React from ‘expo:react’ And not pay the cost of parsing the JS bundle. You wouldn’t be able to OTA new versions of React, but that’s tolerable since react rarely changes and you probably don’t want to push duplicate bytes over the air each time. It was configured by the bundler so you could change which modules which built-in to your native binary. The result was radically smaller JS updates, faster bundling, better performance in development mode, and more sensible debugging. Still thinking about what RN would be like if it pushed more JS into the runtime instead of always defining it in user land.