There are two gems you are going to need for this: guard and guard-livereload

Install both of them, then cd into your Ruby app folder. Then you have to compile a file, called a Guardfile.

guard init livereload

That’s it! Now you when you have your app running, open a new terminal window and type:

guard

now every time you make a change your ruby app files, guard automatically reloads the app!

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