This chapter has shown you how to introduce React Router in a testable fashion. We made extensive use of shallow rendering, and you've seen how to use both routing and query string in place of states.
Now that we've successfully refactored to one library, the next one shouldn't be too tricky, right? In the next chapter, we'll apply all the skills we've learned in this chapter in another context. We'll refactor our codebase to use what's arguably the most cryptic of React libraries: Redux.