Here are some common issues that people run into and their solutions.
You're seeing an exeception page which says
Undefined mixin 'theme-colors'.
This happens when you have a
require_tree in your
application.css, and you missed the instructions telling you to remove it.
require_tree loads files in a random order and in this case it's loading some of the SCSS files before the file that defines the mixins.
require rrt. You might need to add explicit imports for any other files that were previously being automatically included randomly via
You're seeing an exception being thrown with the message
can't find gem bundler (>= 0.a) with executable bundle when trying to deploy to Heroku or other environments.
You're using a version of Bundler greater than 2.0. Bundler 2.0 introduced several breaking changes and you should be aware of them https://bundler.io/blog/2019/01/03/announcing-bundler-2.html
Implement the Bundler 2.0 scheme for handling your existing