In this chapter, you put together a simple book manager Redux app. With the app in place, you then learned how to install the Redux DevTools browser extension in Chrome. From there, you learned how to view and select actions.

There are a number of ways to view information about the application once you've selected an action. You can look at the action payload data. You can look at the application state in its entirety. You can look at diffs between the app state and the last dispatched action. These are all different approaches you can use to instrument your Redux applications.

Then, you learned how time travel debugging works in Redux DevTools. Because state changes are immutable in Redux, you can use Redux DevTools to jump around from action to action. This can drastically simplify debugging cycles. Lastly, you learned how to manually dispatch actions and import/export the state of your application.

In the next chapter, you'll learn how to use Gatsby to generate static content from React components.