I was trying to use ActionText but Rails was giving me an issue about missing vips command in my Mac.
After a bit of digging, I realized that I have to install libvips. It's a competitor of Imagemagick.
It's easy to do it on a Mac but it will take sometime to load everything.
You just run in your terminal:
brew install vips
Then you go back to your Rails app and run:
That will make sure you have everything you need.