I created an express-based backend (in folder A) and a related react-based front-end project (in folder B) respectively. Now I put B inside A for the following benefits:

1. I don't need to copy files from font-end build to server project anymore because `A/server.js` can serve files from `A/B/build` directly.
2. No need to worry about the cross origin request errors.
3. They look like one project and are easier to manage in GitHub.
But can I run `npm run buildjs` from folder A, which actually runs `npm run build` in folder B? I guess it has much to do with the npm run-script usage.