Pry is an REPL Gem that offers a ton of useful features over IRB.
State is an important aspect of React, and as of 16.8, managing state within your React app is even easier with the use of React hooks.
Ruby’s ^ operator is a nifty operator to use if you need to test whether one (and only one) of the inputs are true.
For the Flatiron School final project, the assignment was to write an application using React/Redux with a Rails API back end. I chose to make an application that pulls data from The Movie DB’s API and displays that to the user.