1. Together with Socket.IO I suggest to add WebSockets concepts 2. Cloud Databases => MongoDB Atlas (www.mongodb.com/cloud/atlas/) - Very useful, fast and Free 3. Message Broker => Redis - Very fast and cool to use, but not so much adopted, you can add as gray color 4. NoSQL => Fundamental (IMHO) 5. Fix: WebFrameworks => Loopback.js should be Loopback.IO instead 6. Add ES2020 (https://alligator.io/js/es2020/) 7. Good to Know => Add SSR (Server-Side Rendering) to learn the concepts used on next.js for example 8. Good to Know => Add SSE (Server-Sent Events) very useful when you need only one-way communication with frontend 9. Good to Know => Clean Code 10. Good to Know => Code Styles (Like Google https://google.github.io/styleguide/jsguide.html or AirBnB https://github.com/airbnb/javascript) 11. API Authentication
