If you see an error like this:
This installation of RMagick was configured with ImageMagick 6.9.1 but ImageMagick 6.9.2-4 is in use.
or
This installation of RMagick was configured with ImageMagick 6.9.2 but ImageMagick 6.9.3-0 is in use. (RuntimeError)
Here’s a possible fix:
export RMAGICK_BYPASS_VERSION_TEST=true
gem uninstall rmagick && gem install rmagick
bundle