Hey @JesperCorba You can create a local module within your project that both App.js and Server.js can require/import. You can structure your project with a folder for shared code, like /lib or /common, and place your shared JavaScript files there. Then, you can import these modules into both your server and client-side code.
// In /common/mySharedModule.js
module.exports = {
sharedFunction: function() {
// Shared code here
}
};
// In App.js and Server.js
const mySharedModule = require('./common/mySharedModule');