In one terminal:
$ bb shadow-dev
In another terminal:
$ bb expo-start
Then in the expo terminal, type "i" to launch it in the simulator.
Note: disable fast-refresh in the expo dev menu in the app.
$ npx create-expo-app my-app
$ mv my-app expo
$ rm expo/App.js
Then we edited expo/app.json
to set {"entryPoint": "./target/index.js"}
.