Running your application in the cloud gives you the flexibility to reach millions of users from all regions of the globe. When dealing with such scale, you need to know that your application can handle it, and if something goes wrong, then you want to know about it as soon as possible. In this chapter, you learned about some of the tools that will help you control the state of your deployed application. Azure App Service's Scale up and Scale out are two options you can use to make sure your application can reach higher and higher scales and can handle an increase in the number of requests received. You can set your App Service to autoscale out or in based on metrics or other rules that you define. With Azure Application Insights, you can see events happening in your application, query them, and let Application Insights monitor them and alert you to anomalies. Finally, when you make changes and want to make sure they work as expected in the production environment, you can use Deployment slots and swap when you are ready, or you can use the test in production capability and distribute traffic to different slots at the same time so that you can monitor the effects without affecting your entire user base.

Finally, we are here–the last words of the chapter. You've come a long way and have learned many new concepts. Well done!
While reading this book, you have developed a full and complete application that is production-ready. You have worked on both the frontend and backend, have created a domain model and stored it in a database, and have created a cloud environment and configured it to scale. You've also created a fully automated process to deploy your application into production. You are now a real full-stack developer, and we want to take this moment to say thank you and congratulate you on your success. We are sure you will use the techniques you learned in this book to create wonderful applications, and we wish you good luck in the rest of your full-stack career.