This chapter introduced you to the concept of using side-effects from Immutable.js method call chains to render UI elements. We first looked at how to do this using nothing but Immutable.js and native DOM methods. Using the techniques for composing behavior that you learned in Chapter 13, Declarative Decision Making, you composed event handling behavior and filtering behavior for the episodes to render.
You then implemented the same UI using the same Immutable.js techniques, but now using React as the UI component library. In the end, it doesn't matter what tooling you're using in your application—the tools and techniques you've learned about Immutable.js are universally applicable.
In the next chapter, we'll continue our discussion on side-effects, except we'll shift the focus to Node.js environments.