Typically autoload paths configured in application.rb will be like this:
config.autoload_paths += %W(lib)Recently we faced a problem where we were adding another root level folder app
to autoload_paths, and using one of utility classes inside that folder. Everthing
worked fine in development, but not in production. We started seeing strange
errors while running migrations:
cannot load such file -- app/subdir1/utility_class
Inspecting $LOAD_PATH revealed that there is no absolute path for app folder.
Appending autoload_path with absolute path solved this issue.
config.autoload_paths += [ Rails.root.join("app") ]