Discover how to achieve high performance and exceptional user experience in your web applications using fine-grained reactivity with signals. This powerful technique allows you to fine-tune the reactivity of your components, making your applications more efficient and responsive to user interactions. Learn the benefits of using signals, how to implement them, and create highly reactive components that respond to changes in a targeted way, resulting in a better user experience.

In this talk you will know how to share code between the next code bases: Web App, Android application, and Kotlin backend. I will show how to take those 3 applications and iteratively start to share step-by-step: models, data validation logic, request/response services, and even UI. At each step we will have a ready-to-production application and participants could chose any "depth" of the code sharing.

Congrats, you deployed your Node app to prod! But how do you actually know if your users are having a good experience? Logs are great initially—until your dashboard becomes overwhelming. We could add metrics but they have a steep learning curve. In this talk we'll see where console.log falls short and learn how metrics help us better define what a good user experience is. We'll also discuss why useful code instrumentation is hard, and propose what we can do to make it easier.